Forgiveness by God Himself, is different than some human granting you forgiveness (even that of a priest). God’s forgiveness is official in Heaven’s Courts, and so, it lasts forever.
Tolerating evil
If you tolerate bad behavior, you in effect are condoning the bad. The Bible says here that the person who practices or permits or tolerates evil (evil = that which is not of God) cannot possibly be a true follower of Jesus.