John 20:23 says: "If you forgive anyone his sins they are forgiven; if you do not forgive them, they are not forgiven." If after you had sinned against a person and asked to be forgiven, have you received forgiveness even though the person in question did not forgive you?
This scripture needs to be looked at in context of the two preceding scriptures. After Jesus was resurrected, he appears to his apostles and tells them, "As the Father has sent me, I am sending you. And with that he breathed on them and [...]