New Revised Standard Version
You ask, “Why does he not?” Because the LORD was a witness between you and the wife of your youth, to whom you have been faithless, though she is your companion and your wife by covenant.

Contemporary English Version
And why isn't God pleased? It's because he knows that each of you men has been unfaithful to the wife you married when you were young. You promised that she would be your partner, but now you have broken that promise.

New American Bible
And you say, “Why?”— Because the LORD is witness between you and the wife of your youth With whom you have broken faith, though she is your companion, your covenanted wife.

Douay-Rheims Bible
And you have said: For what cause? Because the Lord hath been witness between thee, and the wife of thy youth, whom thou hast despised: yet she was thy partner, and the wife of thy covenant.

And you have said: For what cause? Because the Lord hath been witness between thee, and the wife of thy youth, whom thou hast despised: yet she was thy partner, and the wife of thy covenant.

Wherefore.

Malachi 1:6,7 The son honoureth the father, and the servant his master: if then I be a father, where is my honour? and if I be a master, where is my fear: saith the Lord of hosts. . . .

Malachi 3:8 Shall a man afflict God, for you afflict me. And you have said: Wherein do we afflict thee? in tithes and in firstfruits.

Proverbs 30:20 Such also is the way of an adulterous woman, who eateth and wipeth her mouth, and saith: I have done no evil.

Isaiah 58:3 Why have we fasted, and thou hast not regarded: have we humbled our souls, and thou hast not taken notice? Behold in the day of your fast your own will is found, and you exact of all your debtors.

Jeremiah 8:12 They are confounded, because they have committed abomination: yea rather they are not confounded with confusion, and they have not known how to blush: therefore shall they fall among them that fall; in the time of their visitation they shall fall, saith the Lord.

the Lord.

Malachi 3:5 And I will come to you in judgment, and will be a speedy witness against sorcerers, and adulterers, and false swearers, and them that oppress the hireling in his wages, the widows, and the fatherless: and oppress the stranger, and have not feared me, saith the Lord of hosts.

Genesis 31:50 If thou afflict my daughters, and if thou bring in other wives over them: none is witness of our speech but God, who is present and beholdeth.

Judges 11:10 They answered him: The Lord, who heareth these things, he himself is mediator and witness that we will do as we have promised.

1 Samuel 12:5 And he said to them: The Lord is witness against you, and his anointed is witness this day, that you have not found any thing in my hand. And they said: He is witness.

Jeremiah 42:5 And they said to Jeremiah: The Lord be witness between us of truth and faithfulness, if we do not according to every thing for which the Lord thy God shall send thee to us.

Micah 1:2 The word of the Lord, that came to Micah, the Morasthite, in the days of Joathan, Achaz, and Ezechias, kings of Juda: which he saw concerning Samaria and Jerusalem.

the wife.

Malachi 2:15 Did not one make her, and she is the residue of his spirit? And what doth one seek, but the seed of God? Keep then your spirit, and despise not the wife of thy youth.

Proverbs 5:18,19 Let her be thy dearest hind, and most agreeable fawn: let her breasts inebriate thee at all times: be thou delighted continually with her love. . . .

Ecclesiastes 9:9 Live joyfully with the wife whom thou lovest, all the days of thy unsteady life, which are given to thee under the sun, all the time of thy vanity: for this is thy portion in life, and in thy labour wherewith thou labourest under the sun.

Isaiah 54:6 For the Lord hath called thee as a woman forsaken and mourning in spirit, and as a wife cast off from her youth, said thy God.

thy companion.

Genesis 2:18 And the Lord God said: It is not good for man to be alone: let us make him a help like unto himself.

Proverbs 2:17 And hath forgotten the covenant of her God: for her house inclineth unto death, and her paths to hell.

Songs 1:15 Behold thou art fair, my beloved, and comely. Our bed is flourishing.

.

Ezekiel 16:8 And I passed by thee, and saw thee: and behold thy time was the time of lovers: and I spread my garment over thee, and covered thy ignominy. and I swore to thee, and I entered into a covenant with thee, saith the Lord God: and thou becamest mine.