What is the meaning of Matthew 17:22-23 KJV?

22 And while they abode in Galilee, Jesus said unto them, The Son of man shall be betrayed into the hands of men: 23 And they shall kill him, and the third day he shall be raised again. And they were exceeding sorry. (Matthew 17:22-23 KJV)

William Burkitt’s Commentary

Observable it is, how frequently our Saviour forewarned his disciples of his approaching sufferings. All was little enough to arm them against the scandal of the cross, and to reconcile them to the thought of what he was to suffer for them, and they were to suffer with him.

Learn, That we can never hear too much of the doctrine of the cross; nor can we be too often instructed in our duty to prepare for a suffering condition. As Christ went by his cross to his crown, from a state of abasement to a state of exultation, so must all his disciples and followers likewise.