kjv@Matthew:16:21@ From that time forth began Jesus to shew unto his disciples, how that he must go unto Jerusalem, and suffer many things of the elders and chief priests and scribes, and be killed, and be raised again the third day.
kjv@Matthew:16:22@ Then Peter took him, and began to rebuke him, saying, Be it far from thee, Lord: this shall not be unto thee.
kjv@Matthew:16:23@ But he turned, and said unto Peter, Get thee behind me, Satan: thou art an offence unto me: for thou savourest not the things that be of God, but those that be of men.
kjv@Matthew:16:24@ Then said Jesus unto his disciples, If any man will come after me, let him deny himself, and take up his cross, and follow me.
kjv@Matthew:16:25@ For whosoever will save his life shall lose it: and whosoever will lose his life for my sake shall find it.
kjv@Matthew:16:26@ For what is a man profited, if he shall gain the whole world, and lose his own soul? or what shall a man give in exchange for his soul?
kjv@Matthew:16:27@ For the Son of man shall come in the glory of his Father with his angels; and then he shall reward every man according to his works.
kjv@Matthew:16:28@ Verily I say unto you, There be some standing here, which shall not taste of death, till they see the Son of man coming in his kingdom.
The comment about the leaven of the Pharisees is just as much a observation of what is currently transpiring against Him as it is a doctrinal fidelity teaching. Jesus sees what is developing and the rage mounting against Him so He checks to see how far along the Disciples hearts are in the revelation process. They are currently far enough to know that He is Christ but, not so far as to know what Christ must suffer for them in the very near future. Until they grasp this further more complete revelation they will not grasp their own future pathway - the baring of their own cross for Him in His absence up until His return.
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