23 Therefore if you bring your gift to the altar, and there remember that your brother has something against you, 24 leave your gift there before the altar, and go your way. First be reconciled to your brother, and then come and offer your gift. (Matthew 5:23-24)
The ability to reconcile a problem begins with admitting your part in contributing to the problem. Take responsibility and work to correct the matter. That is what Jesus teaches here. Your “brother has something against you” – you have done something that caused a dispute. Accept your responsibility for the hostility between yourself and your brother (or parent, sibling, neighbor, etc.). Take the initiative to reconcile. If you are unwilling to correct your own faults with another, then God will not accept your worship. We cannot mistreat others and expect God to accept our worship.