Matthew 16:23

But he turned

(ο δε στραφεις). Second aorist passive participle, quick ingressive action, away from Peter in revulsion, and toward the other disciples (Mark 8:33 has επιστραφεις and ιδων τους μαθητας αυτου).Get thee behind me, Satan

(Hυπαγε οπισω μου, Σατανα). Just before Peter played the part of a rock in the noble confession and was given a place of leadership. Now he is playing the part of Satan and is ordered to the rear. Peter was tempting Jesus not to go on to the cross as Satan had done in the wilderness. "None are more formidable instruments of temptation than well-meaning friends, who care more for our comfort than for our character" (Bruce). "In Peter the banished Satan had once more returned" (Plummer).A stumbling-block unto me

(σκανδαλον ε εμου). Objective genitive. Peter was acting as Satan's catspaw, in ignorance, surely, but none the less really. He had set a trap for Christ that would undo all his mission to earth. "Thou art not, as before, a noble block, lying in its right position as a massive foundation stone. On the contrary, thou art like a stone quite out of its proper place, and lying right across the road in which I must go--lying as a stone of stumbling" (Morison).Thou mindest not

(ου φρονεις). "Your outlook is not God's, but man's" (Moffatt). You do not think God's thoughts. Clearly the consciousness of the coming cross is not a new idea with Jesus. We do not know when he first foresaw this outcome any more than we know when first the Messianic consciousness appeared in Jesus. He had the glimmerings of it as a boy of twelve, when he spoke of "My Father's house." He knows now that he must die on the cross.