Jesus conferred on Peter...
Jesus conferred on Peter and the church the power of the keys, the authority to forgive sins in God's name (v. 19). But we are not very good at forgiving. Martin Luther made that clear: "It never fails: at times you do and say something that disgust me, and I do and say something that does not please you at all, just as one member of the body injures another..." (What Luther Says, p. 525).
Part of the problem is that we are not as tough on ourselves as we are with our neighbors. Again Luther offers significant wisdom: