Charles Spurgeon Commentary Matthew 16:21

"From that time began Jesus to show unto his disciples, that he must go unto Jerusalem, and suffer many things of the elders and chief priests and scribes, and be killed, and the third day be raised up." — Matthew 16:21 (ASV)

The Church, or assembly, being now actually arranged and treated as a fact, our Lord began to prepare His disciples for the time when, as an associated body, they would have to act alone, because He would be taken from them. Their first great trial would be His death, of which He had spoken obscurely before. From that time forth began Jesus to shew unto his disciples His death more plainly.

There is a fit time for painful disclosures, and our Lord is wise in selecting it. He mentions the gathering of His foes; elders and chief priests and scribes will eagerly unite. Their fury will show itself in multiplied cruelties. He will suffer many things. He declares that they will push their enmity to the bitter end. He will be killed. He foretells that He will be raised again, and He specifies the time, namely, the third day. All this must have fallen sadly on the ears of men who still indulged visions of a kingdom of a very different sort. Most of them were wisely silent in their sadness, yet there was one who had far too bold a tongue.

He had previously spoken somewhat darkly concerning his death; but it was so sad and so strange a revelation to his disciples that they could not think he really meant quite what he said. But now he began definitely and plainly to tell them about the future, and even to enter into details concerning his death and resurrection.

He knew all that the work of redemption would involve for him; he had counted the cost; but— "When the Saviour knew
The price of pardon was his blood,
His pity never withdrew."

It must have been very saddening, but, at the same time, very profitable to the minds of the apostles to be led by their Lord in this direction.