But even if I am being poured out as a drink offering upon the sacrifice and service of your faith: alla ei kai spendomai (1SPPI) epi te thusia kai leitourgia tes pisteos humon: (Phil 2:30; 1:20; Acts 20:24; 21:13; 2Co 12:15; 1Thes 2:8; 2Ti 4:6; 1John 3:16) (Php 4:18; Ro 12:1; 15:16; Heb 13:15,16; 1Pet 2:5)

Poured out as a drink offering (4689) (spendo [word study]) means to pour out an offering as an act of worship or ritual observance or as a libation. Paul is alluding to his possible martyrdom (which by tradition did become a reality).

The picture of poured out is from OT sacrificial system. As commanded in the book of Numbers, the people of Israel, as well as Gentiles who lived among them, were first to give a burnt offering of one of the prescribed animals, then a grain offering, and finally a drink offering (Nu 15:1-10). Pouring out as a drink offering refers to the topping off of an ancient animal sacrifice. The offerers poured wine either in front of or on top of the burning animal and the wine would be vaporized. That steam symbolized the rising of the offering to the deity for whom the sacrifice was made (cf. Ex 29:38, 39, 40, 41; 2Ki 16:13 ;Jer 7:18 ; Ho 9:4).

In OT sacrificial system this was the final offering that followed burnt and grain offerings prescribed for the people of Israel (Nu 15:1-16).

In Paul's last letter ever recorded, 2Timothy, the apostle pictured his coming death as his final offering to God in a life that had already been full of sacrifices to Him writing that...

I am already being poured out as a drink offering, and the time of my departure has come. (2Ti 4:6-note)

Just as he had offered himself to the Lord as “a living and holy sacrifice, acceptable to God” (see note Romans 12:1) while he was alive, he now offered himself to the Lord in his death. He was

ministering as a priest the gospel of God, that [his] offering of the Gentiles might become acceptable, sanctified by the Holy Spirit (see note Romans 15:16).

Wuest adds...

The words “offered up” (Php 2:17KJV) are the translation of a Greek word used in the pagan Greek religions, of the drink-offering poured out upon the sacrifice itself, the latter being the major part of the offering to the gods, and the former, the minor part. Paul uses this drink-offering or libation to speak of the violent death he will some day die as a martyr. It will be his blood poured out. Indeed, during his second Roman imprisonment, knowing that he would shortly be sent to the executioner’s block for decapitation, he writes to Timothy, using the same word, “For I am now ready to be offered,” or as one could translate, “For my life’s blood is already being poured out” (2Ti 4:6-note). He uses the main sacrifice as an illustration of the Philippian saint’s Christian life and service. The Greek word for “sacrifice” used (Wuest, K. S. Wuest's Word Studies from the Greek New Testament: Eerdmans or Logos)

Sacrifice (2378) (thusia from thúo = to sacrifice) is used metaphorically in the NT referring as here to one's service but also to obedience and praise. Thusia was used for both pagan animal sacrifices and in the Septuagint, (some of the uses of thusia = Ge 4:3, 5; 31:54; 46:1; Ex 10:25; 12:27; 18:12; 24:5; 29:34, 41f; 30:9; 32:6; Lev 1:9, 13, 17; 2:1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15; 3:1, 3, 6, 9; 4:10, 26, 31, 35; 5:13; 6:14, 15, 20, 21, 23; 7:9-17, 15, 16, 17, 20, 21, 29, 32, 34, 37; 9:4, 17, 18; 10:12, 14; 14:10, 20f, 31; 17:5, 7f; 19:5; 21:6, 21; 22:21, 29; 23:13, 16, 18f, 37; 26:31)

Thusia - 28x in 28v - Mt 9:13; 12:7; Mark 12:33; Luke 2:24; 13:1; Acts 7:41, 42; Ro 12:1; 1 Cor 10:18; Eph 5:2; Phil 2:17; 4:18; Heb 5:1; 7:27; 8:3; 9:9, 23, 26; 10:1, 5, 8, 11f, 26; 11:4; 13:15, 16; 1 Pet 2:5.

Service (3009) (Leitourgia) (see word study of verb Leitourgeo) was used for used of the religious service of the Old Testament priests  the religious service of the Old Testament priests.

Leitourgia - See the Septuagint, where leitourgia used in Ex 38:21; Nu 4:24, 27f, 33; 7:5, 7f; 8:22, 25; 16:9; 18:4, 6f, 21, 23, 31; 2Sam 19:18; 1 Chr 6:32, 48; 9:13, 19, 28; 23:24, 26, 28; 24:3, 19; 26:30; 28:13, 20f; 2 Chr 8:14; 31:2, 4, 16; 35:10, 15f; Ezra 7:19; Ezek 29:20

Williams comments

The apostle compares the self-sacrifice and energy of the Philippians with his own, magnifying theirs and minimizing his. They were both laying down their lives for the sake of the gospel, but their action he regards as the great sacrifice, and his as only the drink offering poured out upon it. Under this beauteous figure of speech, he speaks of his possible approaching death as a martyr. (George Williams, The Student’s Commentary on the Holy Scriptures, p. 931)

Wuest adds

What humility for the great apostle to rejoice at the fact that some day he would be the lesser part of the sacrifice poured out upon the major part, the Philippian’s Christian testimony and service to God.   (Ibid)

Leitourgia -  6x in 6v - Luke 1:23; 2 Cor 9:12; Phil 2:17, 30; Heb 8:6; 9:21. NAS = ministry(2), priestly service(1), service(3).

The writer of Hebrews gives us a proper perspective on service...

Through Him (Christ, our Great High Priest) then, let us continually offer up a sacrifice of praise to God, that is, the fruit of lips that give thanks to His name. And do not neglect doing good and sharing, for with such sacrifices God is pleased. (He 13:15, 16-note)

William Plummer...

The Scriptures do commend a very high degree of love to men. They say that "perhaps for a good man some would even dare to die." Ro 5:8-note. This is evidently spoken not in censure, but in praise of the self-sacrificing man. John is yet more explicit, and says that in certain cases "we ought to lay down our lives for the brethren." 1John 3:16. Paul furnishes us with an example of what John here teaches when he says to the Philippians, "If I be offered upon the sacrifice and service of your faith, I rejoice with you all." Phil 2:17. Now Paul did not love others more than the law requires; yet he was willing to suffer martyrdom, if thereby he could be most useful to his fellow-men. Surely this is loving our neighbor as ourselves. The thing is therefore not impracticable. Greater love than this is not required. (Vital Godliness)

I rejoice  and share my joy  with you all: chairo (1SPAI) kai sugchairo (1SPAI) pasin humin:   (2Co7:4; Col 1:24; 1Th3:7, 8, 9)

Paul would gladly be poured out in martyrdom on the sacrifice and service of their faith.  If this should be his lot, he would rejoice that it should be so.

Rejoice (5463) (chairo) means to be be cheerful and to enjoy a state of happiness and well-being.

Share joy (4796) (sugchairo from sun = together, speaks of an intimate union + chaíro = rejoice) means to rejoice together and thus to share in another’s joy.

David Black...

To animate us to the exercise of pure and unselfish zeal, let us recall to our minds the example of the best and holiest men who have lived in past ages.

"All seek their own interests, not those of Jesus Christ." And too much cause has there been for the same complaint in every period of the church. But, blessed be God, there have been and still are many noble examples of the contrary spirit. The Lord has not lacked faithful witnesses to his truth, from the earliest ages of the world through all succeeding generations to the present times. But in none was this blessed temper ever more conspicuous, than in Paul himself, the apostle whose words we are now considering. How ardent and unselfish was the zeal of this great apostle, for the honor of his Master! From the time that his Lord met him on his way to Damascus, to the close of his life, a period of more than thirty years, his whole soul was engaged in devising and carrying into execution schemes for the advancement of the Redeemer's kingdom. Sometimes the apostle met with ungrateful returns from those whose best interests he labored to promote; but even ingratitude itself could not damp the generous ardor of his love. Speaking to the Corinthians, he says, "I will most gladly spend and be spent for you. If I love you more, am I to be loved less?" (2Cor 12:15)

In the prosecution of this arduous work, the apostle was sometimes exposed to incredible dangers and hardships. But none of these things moved him, neither did he count his life dear to himself, that he might finish his course with joy. Yes, says he (Phil. 2:17), and if I am offered upon the sacrifice and service of your faith, I joy and rejoice with you all. (The Duty of Seeking the Things Which Are Jesus Christ)

You too I urge you rejoice in the same way: to de auto kai humeis chairete (2PPAM): (Php 3:1; 4:4; Ep 3:13; Jas1:2, 3, 4)

I urge - Not in the Greek but added for clarity.

In the same way (KJV "for the same reason") -  The Philippians should be glad and rejoice with Paul and so he commands them to do so. They should not look on his possible martyrdom as a tragedy but congratulate him on such a glorious departure.

Both verbs (rejoice and share joy) are present imperative commanding this to be their lifestyle.

By way of application to our daily Christian life which is to be a joy filled testimony (See Ps 16:11-note,  Jn 15:11,16:24, 17:13, 2Ti 1:4-note, cp 1Pe 1:8-note, 1Jn 1:4, 2Jn 1:12) to a deeply despairing (no hope) world, simply try to do this in your own strength, your natural energy! You might succeed for a moment or two but for this to be one's lifestyle requires continual dependence upon a supernatural Source, and calls for the believer to continually submit to the control of the Holy Spirit (cp Eph 5:18-note, Gal 5:22-note)

Rejoice (5463) (chairo) means to be be cheerful and to enjoy a state of happiness and well-being.

Chairo - 74x in 68v -Matt 2:10; 5:12; 18:13; 26:49; 27:29; 28:9; Mark 14:11; 15:18; Luke 1:14, 28; 6:23; 10:20; 13:17; 15:5, 32; 19:6, 37; 22:5; 23:8; John 3:29; 4:36; 8:56; 11:15; 14:28; 16:20, 22; 19:3; 20:20; Acts 5:41; 8:39; 11:23; 13:48; 15:23, 31; 23:26; Rom 12:12, 15; 16:19; 1 Cor 7:30; 13:6; 16:17; 2 Cor 2:3; 6:10; 7:7, 9, 13, 16; 13:9, 11; Phil 1:18; 2:17f, 28; 3:1; 4:4, 10; Col 1:24; 2:5; 1 Thess 3:9; 5:16; Jas 1:1; 1 Pet 4:13; 2 John 1:4, 10f; 3 John 1:3; Rev 11:10; 19:7. NAS =  am glad(1), glad(7), gladly(1), greeted*(1), greeting(2), greetings(3), hail(5),joyfully(1), rejoice(33), rejoiced(8), rejoices(2), rejoicing(10)

and share your joy with me:  kai sugchairete (2PPAM) moi:

Share...joy (sugchairo from sún = together + chaíro = rejoice) means to rejoice together and thus to share in another’s joy. What a great thing to share!

F B Meyer...

THE SACRIFICIAL SIDE
OF THE CHRISTIAN LIFE
Phil 2:17, 18

AGAIN the Apostle refers to the "day of Christ." He was constantly anticipating the coming of the Lord. His early Epistles specially abound in references to that event which would bring to light the hidden things of darkness, and make manifest the counsels of all hearts, so that each man should have his praise from God. He spoke of his being alive and remaining unto the coming of the Saviour, and as anticipating that his mortality would be swallowed up of life. Often, amid his imprisonment, he must have listened for the sounding of the trumpet of God, and the songs which accompanied his returning Lord. Invariably he so lived and laboured, that whenever that day came, whether to close his earthly life or afterwards he might receive the reward, which would be to him what the crown of amaranth was to the successful competitor in the games.

Paul's Great Fear. Paul's incessant fear was that he might run or labour in vain. There are many expressions of it. In one place he expresses the fear lest all the work which he had built upon the foundation, which God had previously laid, should be burned up, and he should suffer loss; in another he gives utterance to the dread lest he should be a castaway (or rejected) as one who had no right to the prize; here, he uses the words "in vain" as though some mistake on his part should obliterate all the results of the work, which he had laboriously sought to achieve for his Lord.

How is it with us? A very solemn inquiry is suggested to us all. Are we running in vain? Are we labouring in vain? Life is full of running to and fro, and incessant labour, but we may gravely ask whether at the end there will be aught to show commensurate with the energy we have expended. So many days are lived in vain! So many books are written in vain! So many sermons preached in vain! So many philanthropic activities expended in vain!

A Condition of Success. It is, however, certain that before any service that we do for God or man is likely to be of lasting and permanent benefit, it must be saturated with our heart's blood. That which costs us nothing will not benefit others. If there is no expenditure of tears and prayer, if that love, of which the Apostle speaks in another place, which costs, is wanting, we may speak with the tongues of men and of angels, may know all mysteries and all knowledge, may bestow all our goods to feed the poor, but it will profit nothing. Let us rather seek to be poured forth as a libation than to do much without feeling the least travail of soul. As the fertility of Egypt in any year is in direct proportion to the height that the waters of the Nile measure on the Nilometer, so the amount of our real fruitfulness in the world is gauged by the expenditure of our spiritual force.

It was because Moses was prepared to be blotted from the Book of God for his people that he carried them for forty years through the desert, and deposited them on the very borders of the Promised Land. It was because Jesus wept over Jerusalem that He was able to send a Pentecost on the guilty city. It was because Paul was prepared to be accursed for his brethren according to the flesh, that he was able to turn so many from darkness to light, and from the power of Satan unto God. It is when Zion travails that she brings forth her children. No heart pangs, no spiritual seed.

The Call for Sacrifice. The Christian life should be a sacrifice. Where faith in Christ is a reality, it will lead not simply to a life service, which becomes a liturgy, but also to sacrifice. "I beseech you, therefore, brethren, by the mercies of God to present your bodies a living sacrifice, holy, well-pleasing to God, which is your reasonable service."

There is only one sacrifice which can take away sin, and which was offered once for all. "When He had offered one sacrifice for sins, forever He sat down on the right hand of God": "By one offering He hath perfected forever them that are sanctified." But the whole Church of God is called to follow the Master's steps in the sacrifice of her life for men. She must fill up that which is behind of the sufferings of Christ; she must be prepared to suffer with Him; she must surrender the joy that is set before her of ease, and luxury, and earthly power, in order that she may go out to her Lord without the camp, bearing His reproach. He is the Lamb of God which taketh away the sin of the world, and by His one sufficient sacrifice has opened the way into peace, but there is a sacrifice of what the world deems choicest and best in order that the highest interest of men should be better served, which is the peculiar prerogative, not only of the Church of Christ collectively, but of each individual soul.

Have we our Sacrifice? Is there sacrifice in your life and mine? I knew, for instance, of the case of a young girl, who promised her mother upon her dying bed, that she would not accept an offer of marriage until she had seen the younger children well started in life, and had performed the last offices for her father. I do not here comment upon the unwisdom of a mother exacting such a pledge from her child, but only cite the fact. As a result, when, three years after her mother's death, Love looked into the window of that girl's soul, and one who was altogether suitable for her asked her to be his wife, she felt bound to refuse, and nobly stood by her charge until the whole family passed out of her care into homes of their own. It was a supreme relinquishment of all that a woman holds dearest, but how noble it was!

Is not sacrifice of this sort constantly being demanded of us, have we not all to turn from the doors that stand wide open on our mountains of transfiguration, in order to descend into the valley, where the cross of self-denial stands with wide-open arms, awaiting us? Whenever such is the case, our faith is working out in sacrifice, our obedience to the will of God is enabling us to surrender all things, that we may more efficiently do the high work of Jesus for others. We may well doubt whether we are true followers of the Crucified, or have entered into any true experience of His religion, unless there is the trace of the Cross somewhere, whether known to men, or known only to Christ.

When a deluded man set himself up as the Christ of to-day, the indignant crowd that gathered around the doors of his church demanded that he should show them his hands, meaning that if he were the Christ, the marks of the nails would certainly be apparent. It was a just request. People know well enough that Christ stands for sacrifice, and that His followers can expect no better treatment than He experienced. And again we may put the question to ourselves: Does our faith cost us anything, and is our service to man and God often sealed by blood?

Paul Ready to be Offered. The Apostle was willing to yield his life's blood as a libation. Moses said, "He that offereth his oblation must offer wine for the drink offering, the fourth part of an hin shall he prepare with the burnt offering or for the sacrifice, for each lamb" (Nu. 15:5). This was doubtless in the Apostle's mind when he spoke of being poured out as a drink offering upon the sacrifice and service of their faith.

What unity there was between his sufferings in Rome and theirs in Philippi! It seemed to him as though they had reached a common altar, and were engaged in one common act of devotion. Not only did their faith lead them to considerable sacrifice in order to supply his needs, but it was likely to extort a still greater surrender, even of life itself in the defence of the truth; but in that same cause it was not improbable that sooner or later he would have to shed his blood. There was indeed an if in the case. "If I am offered," etc., but whilst Nero was on the throne, and the hatred of the Jews so virulent, there was little hope that he would escape.

The prospect, however, did not fill him with dread. On the contrary, he anticipated it as though it were a marriage. The thought that he was consummating the faith and service of the Philippians, who had first learnt to love God through his ministry, was a cause of infinite delight.