"And I tell you, you are Peter, and on this rock I will build my church, and the gates of hell shall not prevail against it." Matt. 16:18
"He turned and said to Peter, 'Get behind me Satan! You are a stumbling block. For you are not setting your mind on the things of God, but on the things of man.'" Matt. 16:23
Even the rock of the church was not above becoming a stumbling block, to himself as well as others. It is important to note that although Peter was not Satan, he was exhibiting the satanic mind and mood: "you are not setting your mind on the things of God." At bottom the satanic mind and mood is simply a matter of looking to something other than God, whether it be circumstances, peers, or ourselves. For Satan, he looked to himself (Is. 14:12-14; Eze. 28:12-19). For Peter, he looked to his fellow man and their ideas of what Messiah should be. He rebuffed Jesus for His claim to death, and thought that he was doing the right thing, and therein lies the snare. The satanic mind is more often than not good intentions about completely wrong things, and only a divine rebuke can snap us out of it.
-Jon Vowell (c) 2011