Albert Barnes Commentary Matthew 16:22

"And Peter took him, and began to rebuke him, saying, Be it far from thee, Lord: this shall never be unto thee." — Matthew 16:22 (ASV)

Then Peter took him. This may mean, either to interrupt him, or to take him aside, or to take him by the hand, as a friend. The latter is probably the true meaning. Peter was strongly attached to him. He could not bear to think of his death.

He expected, moreover, that he would be the triumphant Messiah. He could not bear, therefore, to hear that his death was so near. In his ardor, confidence, and strong attachment, he seized him by the hand as a friend and said, Be it far from you. This phrase might have been translated, "God be merciful to you; this shall not be to you." It expressed Peter's strong desire that it might not be.

The word rebuke here means to admonish, or earnestly to entreat, as in Luke 17:3. It does not mean that Peter assumed authority over Christ; but that he earnestly expressed his wish that it might not be so. Even this was improper. He should have been submissive and not have interfered.