Dear sister,
Undoubtedly you know by now that if John is a believer in Christ, has has no freedom to leave, or do anything but honor your marriage. If he's not a believer and choses to leave, let him go. (1 Corinthians 7:15), but if he is a believer, he is bound to you. (1 Corinthians 7:10-11), as we all know God hates divorce (Malachi 2:16), and him leaving, and divorcing you would constitute adultery (Matthew 19:8-9).
So my prayer is the same one I prayed for myself. (with the persons changed obviously...)
Lord,
Speak to the heart of John, and draw him to your will, silence the voice of Satan, and let the voice of you Lord be the only one that is heard. Lord give John no peace in his pursuits, give him no rest in his wickedness and sin. Make every thing he sees and hears Lord be a reminder of you, and of his covenant. Father I ask that you pursue this lost soul, and give him no rest, or favor until he gives in to your will. Lord may this marriage be saved for your glory!
Lord for this wounded sister, I pray for your comfort, and guidance. She is going through a pain too many of us know. I don't know the circumstances exactly Lord, and likely she doesn't either. But Lord, whatever the depth of the pain and anguish this hurt sister is going through, repay her with joy, comfort, and love. Lord if this husband of hers is not a believer, make it obvious to her, and give her the peace she needs to move on. Silence those judgemental voices that will speak out against her in this matter, not knowing the details she will get the stares and comments that run some of us out of your house. Lord keep this sister in a special place where she doesn't even have to turn to you, to have you there. Let your presence surround her through your people, and your spirit.
Lord I pray for the friends and family of this couple. The damage done by this man if he pursues a divorce will extend far beyond just husband and wife, to the parents and in laws if they still live, and brothers, sisters, children, aunts, uncles, cousins, I could go on and on, so many people are wounded by those that give in to the temptation of the evil one, Lord I pray that you cover these people in your grace and comfort, and give them what is needed to end the suffering and pain. In Jesus name,
Amen...