Luke 9:43

And they were all astonished at the majesty of God.

They had seen only Jesus Christ, and this does not mean that the multitude hailed Jesus as God; but what it does mean is that Luke, the sacred author, recognized Christ as God, describing the glory they gave to Jesus, and identifying it as hailing the "majesty of God."

But while all were marvelling at all the things which he did, he said unto his disciples, Let these words sink into your ears: for the Son of man shall be delivered up into the hands of men. But they understood not this saying, and it was concealed from them, that they should not perceive it; and they were afraid to ask him about this saying.

THE PREDICTION OF HIS PASSION

This is another prediction of Jesus' sufferings, death, and resurrection. Matthew recorded Jesus' teachings on this subject three times (Matthew 16:21; 17:22, and Matthew 20:17), each time in a different context; and there is no profit in trying to link Luke's account here with this or that occasion mentioned by Matthew. Jesus repeatedly, over and over again, stressed the thought in view here. See under those references in my Commentary on John for a detailed study of Jesus' announcement of his Passion.

It was concealed from them ... It was God's will that the apostles, while being so thoroughly briefed on all that would take place, should also fail to "get it," as we might say. This seems to be a hint here that they were providentially prevented from understanding it; but it is more likely that the very conception of human salvation as something which Almighty God alone could achieve, and that even he could not achieve it without the death of the Beloved on the cross - that such a colossal truth was utterly beyond the power of the natural man to understand it until after the fact. The concealment was not due to the design of God but to the limitations of men.