If in the original Greek is a first class condition which assumes that what follows is true and therefore could be translated since you have died because if you are a believer you have been co-crucified with Christ. And so here Paul is repeating a truth believers seem to too often forget...

For you have died and your life is hidden with Christ in God. (see note Col 3:3)

Have died (599) (apothnesko from apo = marker of dissociation implying a rupture from a former association,  separation, departure, cessation + thnesko = die) literally means to die off and can speak of physical death but in this context speaks figuratively (metaphorically) of a believer's death to sin, self, the law and the world (see below) that occurred when Christ was crucified and we were crucified with Him (see note Ro 6:6).

Apothnesko is in the aorist tense indicates a past completed event and indicative mood which speaks of a real or actual event. 

What happens when you died? To die means to be separated or to be free of something. What would the Colossians be free of in context of the present discussion? The Law. Believers

"are not under law, but under grace." (see note Ro 6:14)

The preposition apo (in apothnesko) emphasizes the alienation and separation from human ordinances which the believer’s co-death with Christ has brought about. Our life is now hidden with Christ in God (see note Col 3:3), and to live under ordinances of human origin is to live as if in the world and not as if in Him.

In Romans Paul teaches that

we have been buried with Him through baptism into death, in order that as Christ was raised from the dead through the glory of the Father, so we too might walk in newness of life.  (See note Romans 6:4).

The picture Paul is painting is that of the believer's identification or union with Christ in His death, burial and resurrection. (See discussion of "Crucified with Christ - Galatians 2:20)

So what is his point? Paul's reasoning is that because of these great liberating truths, a believer does not have to live like a spiritually dead man but can now live as one alive in Christ, empowered with His resurrection power (note Ro 6:4), energized by the indwelling Holy Spirit (see notes Ephesians 3:16; Ephesians 5:18).

Dying with Christ means not only identification with Him but dying from or to something = sin (see note Ro 6:2), self (2Cor 5:14, 15), the law (see note Ro 7:6; cf Gal 2:19).

In Galatians 6:14, although the verb is different (crucified instead of died) the truth is similar, Paul reiterating that believers are also dead to the world for through...

the cross of our Lord Jesus Christ... the world has been crucified to [us], and [we] to the world. (Gal 6:14).

In (Gal 6:14) the perfect tense indicates a past completed action at a specific point in time with continuing effect, and pictures the lasting effect of our death to the world. Why do so many believers continue to make friends with the world? (cf James 4:4)

In each of these preceding verses (Ro 6:2, 2Co 5:14, 15, Ro 7:6; Gal 2:19) the tense of the verb apothnesko is aorist which signifies a decisive, final death (to sin, self, law, world).

TO THE ELEMENTARY PRINCIPLES OF THE WORLD: apo ton stoicheion tou kosmou:

He has set you free from the evil powers of this world (NLT)

To is the Greek preposition apo which as discussed above is a marker of dissociation and implies a rupture of a former association. It pictures a  separation, a departure or a cessation.

Elementary principles (4747) (stoicheion) refers to the basic components of something, as for example the basic elements from which everything in the world is made and of which it is composed. Stoicheion refers to the rudimentary elements of anything or what belongs to a basic series in any field of knowledge. For example, in grammar, the ABCs, in speech, basic sounds, in physics, the four basic elements (earth, air, fire, water), in geometry, the axioms and in philosophy, the givens. As used in this verse it is a religious technical term making reference to elementary doctrines, fundamental teachings or basic principles .

Paul's point is that the basic lusts of this world (cf 1Jn 2:17) which once held sway over us when we were lost and "in Adam" (see note Ephesians 2:2) has been stripped of their power to control us as result of Christ's death on the Cross and our crucifixion with Him (Gal 6:14).

Paul did not say we would necessarily feel like we had died to these elementary principles. Feelings don't change what is now true of every saint in Christ. This truths define our position and our goal is work our our position in our everyday practice. We are to accept (believe) these things as true about us and to live accordingly under grace not law.

The Colossian saints had been freed is the rudiments of the world, the elementary religious teachings advocating salvation by good works. Since the gospel has freed the believer from attempting to gain heaven by self-effort, he should never subject himself again to legalistic ordinances...don't try to gain God's acceptance and pleasure by self-effort. What motivates you to usher, to sing, to teach, to serve in any capacity at your church?

In Col 2:20-23 Paul proceeds to give instruction as to the right attitude of the true believer to Christ, first pointing out the wrong attitude (that enjoined by the erroneous teachers), that of adherence to rules (v20-23), then, with positive instruction, exhorting the saints to direct their thoughts and energies toward Christ Himself, living, risen and ascended (see note Col 3:1-2).

Peter describes how a "dead" person in Christ should now live (see note 1Peter 4:1-4).

Paul addresses a similar issue in his letter to the Galatians writing that

while we were children ( Before our “coming of age” when we came to saving faith in Jesus Christ), were held in bondage under the elemental things (from Greek word meaning “row” or “rank” and used to speak of basic, foundational things like letters of the alphabet and here as reference to basic elements and rituals of human religion - they were elemental because they are merely human, never rising to the level of the divine) of the world. (Gal 4:3)

Paul goes on to add the contrast that 

But now that you have come to know God, or rather to be known by God (i.e., they were saved), how is it that you turn back again to the weak and worthless elemental things (things connected with the law, such as circumcision, holy days, and rules of diet), to which you desire to be enslaved all over again? (Gal 4:9)

World (2889) (kosmos from komeo = tend, take care of <> English cosmetic = basic meaning of covering up disorder with something that brings order) refers first to an orderly arrangement.

In the New Testament, more often  (as in this verse), kosmos refers not to the physical earth or universe but to the spiritual reality of the man-centered (humanistic) , Satan-directed system of this present evil age, which is alienated from and hostile toward God and God’s people. Kosmos represents the self-centered, godless value system and "ethical" mores of fallen mankind. The goal of the world is self-glory, self-fulfillment, self-indulgence, self-satisfaction, and every other form of self-serving.

Perhaps the question will arise in some minds:

If a Christian is dead to ordinances, why does he still retain baptism and the Lord’s Supper?

The most obvious answer is that these two ordinances of the Christian Church are taught in the NT. However, they are not “means of grace,” making us more fit for heaven or helping us to gain merit before God. Rather, they are simple acts of obedience to the Lord, indicating respectively, identification with Christ and remembrance of Him in His death. They are not so much laws to be kept as privileges to be enjoyed, motivated by our love and respect for God.

WHY AS IF YOU WERE LIVING IN THE WORLD DO YOU SUBMIT YOURSELF TO DECREES SUCH AS: ti os zontes (PAPMPN) en kosmo dogmatizesthe (2PPPI): (Jn 15:19; 17:14-16; 2Cor 10:3; Js 4:4; 1Jn 5:19) (14,16; Gal 4:3,9-12 Heb 13:9)

In other words Paul is saying why

"as though finding all your interests, enjoyments and aims as those do who know not God and are without Christ."

Living (2198) (zao) is not merely existing or dwelling, but possessing a life the very essence of which is relationship with Christ, Who came to give life and to give it abundantly (Jn 10:10). This quality of life has moral associations which are inseparable from it, such as holiness and righteousness. As death and sin are associated in Scripture and in experience, so are life and holiness.

The saints at Colossae were being told that it was wrong to eat certain foods, etc. They were told that keeping these man-made rules was the key to spirituality. The practices Paul is alluding to appear to be forms of asceticism and legalism.

Asceticism is the teaching that spirituality is attained through renunciation of physical pleasures and personal desires while concentrating on “spiritual” matters. It describes the practicing of strict self-denial as a measure of personal and spiritual discipline. Asceticism often proceeds on the assumption that the physical body is evil and is ultimately the cause of sin but this is not a biblical concept.

The Columbia Encyclopedia says that asceticism involves...

"rejection of bodily pleasures through sustained self-denial and self-mortification, with the objective of strengthening spiritual life. Asceticism has been common in most major world religions, including Buddhism, Hinduism, Islam, Judaism, and Christianity: all of these have special ascetic cults or ascetic ideals. The most common ascetic practice is fasting, which is used for many purposes—to produce visions, as among the Crow; to mourn the dead, as among various African peoples; and to sharpen spiritual awareness, as among the early Christian saints. More extreme forms have been flagellation (see flagellants) and self-mutilation, usually intended to propitiate or reach accord with a god." (The Columbia Encyclopedia)

The International Standard Bible Encyclopedia adds that ...

Asceticism is not easily defined because of its diverse manifestations, but in general it involves self-deprivation and is usually pursued out of a desire to glorify God by avoiding what is harmful and by limiting oneself to what is necessary to maintain life. It is unfortunately susceptible to the danger that the pursuit may become subtly diverted to a desire to outstrip one’s fellows and to be credited with a holiness of life unattained by ordinary mortals. These spiritually elite, in turn, may seek to dominate other lives. “There is no pride like that which bases on ascetic austerity the claim to direct with authority the life and conduct of others” (James Denney). (Bromiley, G. W. The International Standard Bible Encyclopedia, Revised. Wm. B. Eerdmans)

Legalism refers to an emphasis on man-made rules and prohibitions as the standard for spirituality. Have you been around people like this? The specific rules and prohibitions may be different today, but the error is the same. And so people come into the body of Christ and tell you how wrong it is to drink alcohol, to watch secular movies, to play cards, to wear make-up or fashionable clothes, to listen to secular music, to dance, and on and on. These individuals are not only convinced that these practices are wrong but consider it as their duty to judge you as unspiritual because you do them!

Nelson's New Christian Dictionary says that legalism is a...

Moral attitude that identifies Christian morality with the literal observance of biblical laws and claims superiority in so doing. The allegation of legalism is often leveled at Christians who believe that God’s Word in Scripture gives specific teaching against certain actions and behavior. (Kurian, G. T. Nelson's new Christian dictionary: Nashville, Tenn.: Thomas Nelson)

Legalism tends to promote self-righteousness and pride and hypocrisy, which are some of the most hateful attitudes to God (Mt 23:25,26)!

Legalism commonly denotes preoccupation with form at the expense of substance.

Legalism needlessly alienates non-Christians. It misrepresents God as a Cosmic Killjoy instead of the Giver of Abundant Life. It implies that we have to clean ourselves up morally before we can come to Christ, instead of coming to him as we are and allowing him to change us from the inside out. It creates ghettoes of finger-pointers instead of people like Jesus, who never compromised morally, but loved lost people and became known as "the friend of sinners."

Legalism and asceticism do not work to make one more like Christ, Who was the epitome of "spirituality" and perfect righteousness!  These genre of "religiosity" may look impressive, but they only manages the outside, the externals and fail to cleanse our inner heart and so fail to liberate us from the control of our sin nature inherited from Adam.

Jesus leveled some of His harshest criticism at the penultimate legalists of His day declaring

"Woe to you, scribes and Pharisees, hypocrites! For you are like whitewashed tombs which on the outside appear beautiful, but inside they are full of dead men's bones and all uncleanness. Even so you too outwardly appear righteous to men, but inwardly you are full of hypocrisy and lawlessness." (Mt 23:27-28)

How then can one achieve control his or her evil desires? The only thing that can control the depraved lusts that originate from our old sin nature inherited from Adam is death. Why? Because death separates. Death liberates. Death frees. In Romans 6 Paul explains that when Christ died, believers died to the power of sin once and for all. It does not matter whether we "feel" like we are dead to sin or not! Scripture teaches that this is now a believer's position (and possession) in Christ and nothing can change that truth. Now our goal is to work out that salvation truth in fear and trembling, knowing that it is still God Who is at work in us to give us the desire and the power to work it out! (see note Phil 2:12) See notes on Romans 6:1-3 for discussion of how to walk in victory (Also see notes on Ro 6:4-5, 6-7,  6:8-10, 6:11, 6:12-14)

Lightfoot paraphrases Colossians 2:20-23 as follows...

"You died with Christ to your old life. All mundane relations have ceased for you. Why then do you—you who have attained your spiritual manhood—submit still to the rudimentary discipline of children? Why do you—you who are citizens of heaven—bow your necks afresh to the tyranny of material ordinances as though you were still living in the world? It is the same old story again; the same round of hard, meaningless, vexatious prohibitions, “Handle not,” “Taste not,” “Touch not.” What folly! All these things—these meats and drinks and the like—are earthly, perishable, wholly trivial and unimportant! They have already been used, and there is an end of them. What is this but to draw down on yourselves the denunciations uttered by the prophet of old? What is this but to abandon God’s word for precepts which are issued by human authority and inculcated by human teachers? All such things have a show of wisdom, I grant. There is an officious parade of religious devotion, an eager affectation of humility; there is a stern ascetic rigor which ill-treats the body. But there is nothing of any real value to check indulgence of the flesh."

What about fasting?

Aren't believers encouraged to fast? The answer of course is yes but it is a qualified "yes" even as our Lord Jesus warned...

And whenever you fast, do not put on a gloomy face as the hypocrites do, for they neglect their appearance in order to be seen fasting by men. Truly I say to you, they have their reward in full. But you, when you fast, anoint your head, and wash your face (see notes Matthew 6:16; 6:17; 6:18)

There are a number of books available on this discipline but many are less than spiritually sound and border on the mystical. In his Preface to A Hunger for God  (excellent resource available online) Dr John Piper gives believers wise counsel regarding the spiritual discipline of fasting writing...

Beware of books on fasting. The Bible is very careful to warn us about people who “advocate abstaining from foods, which God created to be gratefully shared in by those who believe and know the truth” (1 Timothy 4:1-3). The apostle Paul asks with dismay, “Why .. . do you submit yourself to decrees, such as ‘Do not han­dle, do not taste, do not touch’?” (Colossians 2:20-21). He is jealous for the full enjoyment of Christian liberty. Like a great declaration of freedom over every book on fasting flies the ban­ner, “Food will not commend us to God; we are neither the worse if we do not eat, nor the better if we do eat” (1 Corinthians 8:8). There once were two men. One said, “I fast twice a week”; the other said, “God be merciful to me a sinner.” Only one went down to his house justified (Luke 18:12-14).

The discipline of self-denial is fraught with dangers— perhaps only surpassed by the dangers of indulgence. These also we are warned about: “All things are lawful for me, but I will not be mastered by anything” (1 Corinthians 6:12). What masters us has become our god; and Paul warns us about those “whose god is their appetite” (see note Philippians 3:19). Appetite dictates the direc­tion of their lives. The stomach is sovereign. This has a religious expression and an irreligious one. Religiously “persons . . . turn the grace of our God into licentiousness” (Jude 4) and tout the slogan, “Food is for the stomach and the stomach is for food” (1 Corinthians 6:13). Irreligiously, with no pretext of pardoning grace, persons simply yield to “the desires for other things [that] enter in and choke the word” (Mark 4:19).

“Desires for other things”—there’s the enemy. And the only weapon that will triumph is a deeper hunger for God. The weak­ness of our hunger for God is not because he is unsavory, but because we keep ourselves stuffed with “other things.” Perhaps, then, the denial of our stomach’s appetite for food might express, or even increase, our soul’s appetite for God. (Piper, John. available in Pdf online - A Hunger for God)

DO NOT HANDLE: HANDLE:me apse (2PAMS):

Handle (680) (haptomai from from hapto = to fasten to, to connect, bind) means to make close contact and to touch or take hold of something or someone. Haptomai refers to such handling of an object as to exert a modifying influence upon it or upon oneself. Although Paul uses the verb literally in this verse, elsewhere he uses it figuratively meaning to not "touch a woman" sexual sense (see 1 Cor 7:1).

Haptomai involves a conscious effort to touch, an idea that is absent from the other word for touch, thiggano (see below) The NAS picks up the sense translating it "handle". Think for a moment about the distinction between ''handling'' something versus simply ''touching'' it.

The meaning is still further explained in the next verse. These are prohibitions which are manmade, as is indicated by the expression according to the commandments and doctrines (teachings to shape hearer's will) of men.

Paul is describing the essence of the practice of asceticism, an over-developed zeal, a dedication that goes far beyond true Christian discipline and seeks to please God by extreme forms of self-denial. Dedication and discipline are a proper part of the Christian life. You must often make yourself (enabled by grace and the indwelling Spirit) do what God wants you to do, simply because you love him. Love is the proper motive for obedience and the Spirit and grace (in contrast to self effort) is the proper power.

Paul has already commended the Colossians because they led disciplined (see note Colossians 2:5), well-ordered lives. But you can make a god of discipline. You can take perverse delight in making yourself do difficult things that win the approval of others, and (you deceptively imagine), of God as well. As a monk, Martin Luther fell into such empty practices before he became a believer. He would lie naked in his cell all night long in the bitter cold and he beat his body and tortured himself, trying to find peace of heart.

Ray Stedman writes:

"I grew up in Christian evangelical churches that taught there were certain things that Christians must always avoid, and if you observed these taboos you not only were acceptable to the religious community but you were actually pleasing God. I was taught that Christians never drink, never dance, never smoke, never go to movies, never play cards, and never read novels. These prohibitions were usually thundered at us! I do not deny that refraining from some of these things is a perfectly proper discipline of the spirit, but any idea that giving up of things of itself is pleasing to God, is wrong. Christianity is a positive faith. If you want to know what pleases God, read the last twelve verses of Ro 12. You will not find anything negative there. Rather, we are asked to "bless those who persecute you," to love the unlovely and minister to the strangers in our midst. Do things that other people cannot do; that is how true faith is demonstrated."

But what is wrong with fasting until one is close to death, wearing hair shirts, refusing to marry, eating only vegetables, praying by the clock, etc.? Three things:

First, it shows you do not understand your death with Christ. "Since you died with Christ to the basic principles of this world [or, as we saw earlier, "to the elemental spirits of the universe"], why, as though you still belonged to it, do you submit to its rules?" To do so is to return to childish behavior---thinking that God will be pleased by your negative approach to life.

In the church this becomes what we call "legalism," which is to pursue holiness by self-effort, instead of accepting the holiness that God freely gives, by faith, and then living it out in terms of experience. A legalist looks at life and says, "Everything is wrong unless you can prove by the Bible that it is right. Therefore, we must have nothing to do with anything that the Bible does not say is right." That reduces life to a very narrow range of activity. But the biblical Christian looks at life and says, "Everything is right! God has given us a world to enjoy and live in. Everything is right, unless the Bible specifically says it is wrong." Some things are wrong; they are harmful and dangerous. Adultery is always wrong. So is fornication. Sexual promiscuity is wrong. Lying and stealing are wrong. These things are never right. But there is so much that is left open to us. If we are willing to obey God in the areas that he designates as harmful and dangerous, then we have the rest of life to enter into in company with a Savior who loves us, and who guides and guards us in our walk with him.

Secondly, Paul says that whatever benefit these things may gain it is only temporary, it all ends at death.

"These are all destined to perish with use, because they are based on human commands and teachings."

That is why Jesus took the Pharisees to task:

"You observe these minute rituals, but inwardly you are tombs, filled with dead men's bones."

Outwardly you look good, but inwardly you are like a grave full of rotting bones. Your scrupulous refusal to live normal lives gives you certain status and privilege, but it will all prove worthless in the end.

Thirdly, the apostle declares these things are of no value in restraining the indulgence of the flesh. People may outwardly appear dedicated and disciplined, but inwardly sin rages unchecked. Inside they are angry, resentful, filled with vituperation and a spirit of vengeance. Many Christians have this problem. They are trying to regulate the externals instead of walking in the fullness and freshness of life with Jesus Christ, finding the inward purity and cleansing that He alone provides.

All of these errors have one thing in common---they lose the vital relationship we have "in Christ"! If you fall into any, you lose the vitality and vigor of your Christian walk. Life becomes dull and often desperate. Many Christians discover this has happened to them. What they need to do is to return to Jesus (Rev 2:4). When these things take over even here in this place, return to Him. We must take care that every day we are in touch (Col 2:19 "hold fast to the head") with our loving Lord and walking in fellowship with Him. He is the One who can develop the "self-life", and yet keep us from being captured by the great god, "Self". He will restore and comfort us when we fail and falter, and in submission to Him we will find the freedom we seek. (see full message The Things that can Ruin your Faith) (Bolding added)

DO NOT TASTE: mede geuse (2SAMS):

Taste (1089) (geuomai) means to taste with the mouth and is used literally in this verse. Geuomai is used figuratively in Hebrews 6:9 to mean to come to know, which conveys the idea of experiencing something to the full.

Christ had freed them from the taboos of asceticism, which can only give a pretense of wisdom, promote a self-made religion, and deal severely with the body. Yet it cannot succeed in combating the desires of the flesh.

Some would come along and say that if you smoke, you can't be spiritual. C. H. Spurgeon, the "prince of preachers" smoked a big cigar daily until the day he died. At Southwestern Seminary in Ft. Worth, there is a picture of Spurgeon with two fingers painted out because he was holding a stogie and that didn't look very "spiritual"!

One of Spurgeon's "spiritual" friends ask him when he was going to get right with God and stop smoking cigars to which Spurgeon replied:

"When I start smoking to excess."

The "legalist" queried him further:

"What is excess?" to which Spurgeon quipped

"Two at a time!"

The message is that we must be very careful how we handle someone else's supposedly non-conformity. We are all under grace not law (Ro 6:14, Gal 4:9) and grace is not license but balance.

Legalism is largely negative in nature.

Christianity is balanced between God ordained (and empowered) negative and positive aspects.

Denying the body its desires merely arouses them, as is well known by many who have tried to lose weight by sticking to rigid diets. Neglecting the body, Paul argued, does not nourish the spirit. This principle is found in Romans 7 where Paul wrote...

while we were in the flesh, the sinful passions, which were aroused by the Law, were at work in the members of our body to bear fruit for death. (see note Romans 7:5)

DO NOT TOUCH: mede thiges (2SAAS): (Ge 3:3; Isa 52:11; 2Cor 6:17; 1Ti 4:3)

Touch (2345) (thiggano from thigo = to touch) means to come into contact with or to touch

Each of theses negative statements speak of asceticism which is the extreme practice of self-denial. This ca