Amplified: And all the people at the gate and the elders said, We are witnesses. May the Lord make the woman who is coming into your house like Rachel and Leah, the two who built the household of Israel. May you do worthily and get wealth (power) in Ephratah and be famous in Bethlehem.  (Amplified Bible - Lockman)
CEV:  The town leaders and the others standing there said: We are witnesses to this. And we pray that the LORD will give your wife many children, just as he did Leah and Rachel, the wives of Jacob. May you be a rich man in the tribe of Ephrath and an important man in Bethlehem.  (CEV)
GWT: All the people who were at the gate, including the leaders, said, "We are witnesses. May the LORD make this wife, who is coming into your home, like Rachel and Leah, both of whom built our family of Israel. So show your strength of character in Ephrathah and make a name for yourself in Bethlehem. (GWT)
KJV: And all the people that were in the gate, and the elders, said, We are witnesses. The LORD make the woman that is come into thine house like Rachel and like Leah, which two did build the house of Israel: and do thou worthily in Ephratah, and be famous in Bethlehem:
NJB: All the people at the gate said, 'We are witnesses'; and the elders said, 'May Yahweh make the woman about to enter your family like Rachel and Leah who together built up the House of Israel. Grow mighty in Ephrathah, be renowned in Bethlehem!  (NJB)
Young's Literal: And all the people who are in the gate say -- also the elders -- 'Witnesses! Jehovah make the woman who is coming in unto thy house as Rachel and as Leah, both of whom built the house of Israel; and do thou virtuously in Ephrathah, and proclaim the Name in Beth-Lehem;

Septuagint (LXX):   kai eiposan (3PAAI) pas o laos oi en te pule martures kai oi presbuteroi eiposan (3PAAI) doe (3SAAO)  kurios ten gunaika sou ten eisporeuomenen (PMPFSA) eis ton oikon sou os Rachel kai os Leian ai okodomesan (3PAAI) amphoterai ton oikon Israel kai epoiesan (3PAAI) dunamin en Ephratha kai estai onoma en Baithleem
Click here for explanation of verb parsing abbreviations in parentheses after each verb

BBE:  May your family be like the family of Perez, the son whom Tamar gave to Judah, from the offspring which the Lord may give you by this young woman.
CEV:  May the children you have by this young woman make your family as famous as the family of Perez, the son of Tamar and Judah.  (CEV)
GWT: Also, from the descendant whom the LORD will give you from this young woman, may your family become like the family of Perez, the son whom Tamar gave birth to for Judah." (GWT)
KJV: And let thy house be like the house of Pharez, whom Tamar bare unto Judah, of the seed which the LORD shall give thee of this young woman.
NJB: And through the children Yahweh will give you by this young woman, may your family be like the family of Perez, whom Tamar bore to Judah.' (NJB)
Young's Literal: and let thy house be as the house of Pharez (whom Tamar bare to Judah), of the seed which Jehovah doth give to thee of this young woman.'

Septuagint (LXX):   kai genoito (3SAMO) o oikos sou os o oikos Phares on eteken (3PAAI) Tamar to Iouda ek tou spermatos ou dosei (3SFAI) kurios soi ek tes paidiskes tautes

Little did they realize that from this union would issue Israel’s greatest kings including David and the Eternal King, the Messiah, the Lord Jesus Christ.

Why Perez? Probably because he was the offspring of Levirate marriage similar to that of Ruth and Boaz. Tamar was a non-Israelite who became a widow and faced barrenness took into her own hands so to speak the law of goel after the death of two husbands. She was denied levirate marriage to Judah's remaining son Shelah (Gen 38:14). Tamar then invoked deception, disguising herself as a harlot and enticing Judah into a sinful liaison which resulted in the birth of twin boys . Perez, the first born of the twins became the main ancestor of the Ephrathites and Bethlehemites. Tamar and Judah sinned when they acquired a child, but Ruth and Boaz acted righteously and God rewarded them.

THROUGH THE OFFSPRING WHICH THE LORD SHALL GIVE YOU BY THIS YOUNG WOMAN: (1 Sa 2:20)

"Offspring (02233) (zera = seed) ...Jehovah shall give" is testimony to the their understanding that...

"children are a "gift of Jehovah. The fruit of the womb is a reward." (Ps 127:3) (Comment: A truth we have sadly forgotten in America)

Note that the offspring or firstborn would be considered the son of Mahlon and any additional sons born would legally be the offspring of Boaz. Moses explains that...

"And it shall be that the first-born whom she bears shall assume the name of his dead brother, that his name may not be blotted out from Israel." (Deut 25:6)

Young woman (05291) (na'arah) a girl, a young woman or a maidservant. It was used to indicate a young girl who was marriageable as in Genesis, where Moses records Isaac's servant prayer for a wife for Isaac...

BBE:  So Boaz took Ruth and she became his wife; and he went in to her, and the Lord made her with child and she gave birth to a son.
CEV:  Boaz married Ruth, and the LORD blessed her with a son.  (CEV)
GWT: Then Boaz took Ruth home, and she became his wife. He slept with her, and the LORD gave her the ability to become pregnant. So she gave birth to a son. (GWT)
KJV: So Boaz took Ruth, and she was his wife: and when he went in unto her, the LORD gave her conception, and she bare a son.
NJB:  So Boaz took Ruth and she became his wife. And when they came together, Yahweh made her conceive and she bore a son. (NJB)
Young's Literal:  And Boaz taketh Ruth, and she becometh his wife, and he goeth in unto her, and Jehovah giveth to her conception, and she beareth a son.

Septuagint (LXX):  kai elaben (3SAAI) Boos ten Routh kai egenete (3SAPI) auto eis gunaika kai eiselthen (3SAAI) pros auten kai edoken (3SAAI) aute kurios kuesin kai eteken (3SAAI) huion 

The events of at least nine months are described in one sentence of fifteen Hebrew words, including five verbs. We are given no details concerning the kind of marriage ceremony that united Boaz and Ruth. Neither are we told how much time elapsed between their marriage and the birth of their first son.

Ruth went from...

loneliness to love,
toil to rest
poverty to wealth
worry to assurance

despair to hope

And so did you and I the moment the Spirit swept us into the Kingdom of heaven by grace through faith in the satisfactory substitutionary sacrifice of our precious Goel, the Lord Jesus Christ.

Ponder Paul's reminder to the Ephesian Gentiles 

"Therefore remember, that formerly you, the Gentiles in the flesh, who are called "Uncircumcision" by the so-called "Circumcision," which is performed in the flesh by human hands-- remember that you were at that time separate from Christ, excluded from the commonwealth of Israel, and strangers to the covenants of promise, having no hope and without God in the world.

But now in Christ Jesus you who formerly were far off have been brought near by the blood of Christ. For He Himself is our peace, who made both groups into one, and broke down the barrier of the dividing wall, by abolishing in His flesh the enmity, which is the Law of commandments contained in ordinances, that in Himself He might make the two into one new man, thus establishing peace, and might reconcile them both in one body to God through the cross, by it having put to death the enmity. AND HE CAME AND PREACHED PEACE TO YOU WHO WERE FAR AWAY, AND PEACE TO THOSE WHO WERE NEAR; for through Him we both have our access in one Spirit to the Father. So then you are no longer strangers and aliens, but you are fellow citizens with the saints, and are of God's household," (Eph 2:11-19)

AND HE WENT IN TO HER AND THE LORD ENABLED HER TO CONCEIVE AND SHE GAVE BIRTH TO A SON: (Ruth 4:12; Ge 20:17,18; 21:1-3; 25:21; 29:31; 30:2,22,23; 33:5; 1 Sa1:27; 2:5; Ps113:9; 127:3)

"Went (0935) (bow) in to her" is an Old Testament euphemism for sexual intercourse

"The LORD enabled (05414) (nathan = to give) her".

Moses gives a similar testimony to the faithfulness of God writing...

Now the LORD saw that Leah was unloved, and He opened her womb, but Rachel was barren. (Genesis 29:31)

Then God remembered Rachel, and God gave heed to her and opened her womb. (Genesis 30:22)

The gift of children was never taken for granted in Israel. The fact that Boaz and Ruth were able to raise up a son to the deceased Elimelech was evidence of God’s blessing. Ruth had been barren in Moab for the entire period of her marriage to Mahlon (see note Ruth 1:4; 1:5).  Now her faithful obedience was rewarded as God gave her conception. The sojourn in Moab lasted at least 10 years (Ruth 1:4). By contrast, within a few short weeks of their return to Bethlehem, Naomi and Ruth had experienced blessing that was rich and full.

God had been gracious to Ruth back in Moab by giving her the faith to trust Him and be saved. His grace continued when she moved to Bethlehem, for He guided her to the field of Boaz where Boaz fell in love with her. God’s grace continued at the town gate where the nearer kinsman rejected Ruth and Boaz purchased her. After the marriage, God poured out His grace on Ruth and Boaz by giving her conception and then by giving her the safe delivery of a son, whom they named Obed ( means “servant”).

BBE:  And the women said to Naomi, A blessing on the Lord, who has not let you be this day without a near relation, and may his name be great in Israel.
CEV:  After his birth, the women said to Naomi: Praise the LORD! Today he has given you a grandson to take care of you. We pray that the boy will grow up to be famous everywhere in Israel.  (CEV)
GWT:  The women said to Naomi, "Praise the LORD, who has remembered today to give you someone who will take care of you. The child's name will be famous in Israel. (GWT)
KJV: And the women said unto Naomi, Blessed be the LORD, which hath not left thee this day without a kinsman, that his name may be famous in Israel.
NJB: And the women said to Naomi, 'Blessed be Yahweh who has not left you today without anyone to redeem you. May his name be praised in Israel! (NJB)
Young's Literal: And the women say unto Naomi, 'Blessed is Jehovah who hath not let a redeemer cease to thee to-day, and his name is proclaimed in Israel,