Numbers 5:6–7 6 Speak unto the children of Israel, When a man or woman shall commit any sin that men commit, to do a trespass against the Lord, and that person be guilty; 7 Then they shall confess their sin which they have done: and he shall recompense his trespass with the principal thereof, and add unto it the fifth part thereof, and give it unto him against whom he hath trespassed.
To sin against a person is to sin against God. Too often, we take our relationships with others too lightly. Here in Numbers, the trespass (sin) is described as “against the Lord” but then later they are told to repay damages to the one who is harmed. So any sin against man is also a sin against God.
One big way we evaluate our fellowship with God is to evaluate how things are with us and other people. If we have wronged those around us, then we really need to confess our sin to God as well as making things right with those around us.
It reminds us of Psalm 51 where David says to God, “Against thee, thee only, have I sinned…” even though he had committed adultery with Bathsheba and murdered her husband Uriah!