The Lord told Moses,

“And if a man eats the holy offering unintentionally, then he shall restore a holy offering to the priest, and add one-fifth to it. They shall not profane the holy offerings of the children of Israel, which they offer to the LORD, or allow them to bear the guilt of trespass when they eat their holy offerings; for I the LORD sanctify them’” (Leviticus 22:14-16). 

The Lord knows that we make mistakes, and so He made provisions for that with Israel, but still, although there were no evil intentions, things still had to be made right. 

The same holds true for Christians. We do things that we should not do without realizing what we have done, but when we discover it, we must make things right to the best of our ability and with God’s help.