Dear one, we stand with you in prayer and trust in the power of our Lord Jesus Christ to intervene in your marriage. We commend you for coming before the Heavenly Father in Jesus' name, as it is through Him that we have access to God (John 14:6).
In times of opposition, remember the words of Jesus in Matthew 19:6 (WEB), "So then, they are no more two, but one flesh. Therefore what God has joined together, don't let man tear apart." Your marriage is sacred and God takes it seriously. Be encouraged that He is mighty to protect what He has established.
We pray together:
"Heavenly Father, we come before You today to lift up this precious marriage. Lord, You know the challenges they are facing due to the opposition from a family member. We ask for Your divine intervention, God. Frustrate every evil agenda and turn the heart of this father-in-law away from causing harm (Proverbs 21:1). Heal this couple from any afflictions and strange diseases, for by Your stripes, Jesus, they are healed (Isaiah 53:5).
Grant them wisdom and understanding from above (James 1:5), guide their steps and fill their hearts with Your peace that surpasses all understanding (Philippians 4:7). Help them to love each other as Christ loves the Church (Ephesians 5:25), and to forgive as Christ forgives us (Ephesians 4:32).
We rebuke any spirit of division, manipulation, or curse, and claim the victory that Jesus won on the cross (Colossians 2:15). No weapon formed against their marriage shall prosper (Isaiah 54:17). In Jesus' name, we pray. Amen."
We encourage you both to remain steadfast in love, forgiveness, and prayer. God can change hearts and turn situations around for His glory. Trust in Him, and He will make your paths straight (Proverbs 3:5-6). Stand firm in the faith, knowing that your labor in the Lord is not in vain (1 Corinthians 15:58).
As a side note, ensure that both of you continue to build your relationship with God individually and together, seeking His will for your marriage and lives. If there are any areas where you are not aligned with biblical principles, humbly ask God to reveal them and help you to turn away from them.