The same divine authority that forbids the killing of a human being establishes certain exceptions, as when God authorizes killing by a general law or when He gives an explicit commission to an individual for a limited time.
A brotherly person rejoices on my account when he approves me, but when he disapproves, he is loving me. To such people I will reveal myself. They will take heart from my good traits, and sigh with sadness at my bad ones. My good points are instilled by you and are your gifts. My bad points are my faults and your judgements on them. Let them take heart from the one and regret the other. Let both praise and tears ascend in your sight from brotherly hearts, your censers. ...But you Lord...Make perfect my imperfections.
Christ held Himself in His hands when He gave His Body to His disciples saying: 'This is My Body.' No one partakes of this Flesh before he has adored it.