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Marriage is a covenant that brings a couple together both spiritually and physically. Infidelity causes a devastating blow that tears through the oneness of marriage, often resulting in irreparable damage. This can be especially true if a child is conceived through adultery.
A parent’s responsibility to his child is not determined by the circumstances of the child’s conception. Bringing a child into the world through an adulterous act is unfavorable for all parties involved, but it is important to remember that the child is innocent and deserves to have two parents in his/her life.
That child conceived through adultery also has the right to be loved, protected, and provided for. Children are a blessing from God (Psalm 127:3). The child must not be seen as a curse, as a reminder of the sin, or as in any way less worthy. An adulterous affair generates much emotion, vented in many ways, but the child cannot be made the target of spite or ill will.
If the wife decides to remain with her husband even after his affair resulting in a child, she must be prepared to forgive the sin. If the husband decides to remain with his wife who is pregnant with another man’s child, he must forgive the sin. The Bible tells us that Christians are to forgive each other, just as God has forgiven us (Matthew 6:14–15). This means making the choice to put aside the feelings of anger and jealousy.
Ideally, the wife whose husband has fathered a child with someone else will be able to embrace the child as a stepson or stepdaughter, even if the child does not live in her home. She should not stand in the way of her husband forming a relationship with his child, even though this might be painful for her. He has financial, spiritual, and emotional obligations to all his children (Ephesians 6:4).
Conversely, the husband whose wife bears a child by another man should strive to see himself as a stepfather—or even an adoptive father, depending on the living arrangements. Of course, every situation is different, and there are always legal, familial, and personal complexities. But, as believers seek to follow the Lord, their response to adulterous affairs must include measures of forgiveness, grace, love, and peace.
Adultery is a sin with the potential to break up families, but it need not be the end of a marriage. Instead, the couple should work even harder at rebuilding their relationship on the firm foundation of faith and obedience to Jesus Christ. Only the grace and mercy of God and strong faith in Christ will get a couple through this difficult situation. But grace, mercy, and faith are all the gifts of God through the Holy Spirit, and they are available from God to those who truly seek to glorify Him.