We are truly saddened to hear about the abusive situation your son is in. We will stand with you in prayer and offer some biblical guidance.
Firstly, we need to address the abuse. Violence in any form is not acceptable, and it is clear that this relationship is not healthy or honoring to God. The Bible tells us that a wife is supposed to be a "helper" and respect her husband, and a husband is to love his wife, not act violently towards them (Ephesians 5:25-33 WEB). The Scripture also says, "Do not return evil for evil, Husbands, love your wives and do not be bitter against them, but rather, 'If your enemy is hungry, feed him. If he is thirsty, give him a drink;' This is in accordance with the scripture that "Do not be overcome by evil, but overcome evil with good. (Romans 12:20-21 WEB)
It's crucial for your son to understand that this behavior is not acceptable, and he needs to seek God's will for his life and this relationship. At the same time, he must recognize his responsibility to provide for and protect his child, even if that means distancing himself from the abusive situation. God's word says, "If anyone doesn't provide for their own, and especially their own household, they have denied the faith, and is worse than an unbeliever" (1 Timothy 5:8 WEB).
Let's pray together:
"Father, we come before You in the name of Jesus, lifting up this dear son and his situation. Lord, we pray for Your protection over him and his child. We ask that You give him the wisdom and strength to make the right decisions in this abusive relationship. Help him to seek Your will and to act according to Your word. Lord, we also pray for the mother of the child. We pray that You soften her heart and bring conviction upon her for her actions. We ask that You bring healing and restoration to this broken situation. Father, we also lift up the one who submitted this request. Comfort their aching heart and give them the peace that surpasses all understanding. Help them to trust in You and Your promises. We ask all of this in the precious name of Jesus, Amen."
Lastly, we gently remind you that the Bible says, "For there is one God, and one mediator between God and men, the man Christ Jesus" (1 Timothy 2:5 WEB). It is only by the name of Jesus that we have access to God.
Continue to pray for your son and his situation, trusting that God is at work. Encourage your son to seek godly counsel and to surround himself with believers who can support and pray for him.