Cyril of Alexandria

He had shown His glory on the mount to His disciples, and after this delivered a man from an evil spirit, but it was necessary for Him to undergo His passion for our salvation. Now His disciples might have been perplexed, saying, "Have we then been deceived in that we thought him to be God?" That they might know then what was to happen to Him, He bids them lay up in their minds as a certain deposit the mystery of His passion, saying, Let these sayings sink down in your hearts. By the word your, He distinguishes them from others. …

Catena Aurea by Aquinas ↗

Bede

And all were marveling at all that he did, he said to his disciples: Let these words sink into your ears. For the Son of Man is to be delivered into the hands of men. Among the great works of divine power, he often impresses and reiterates the abasement of his human suffering, so that his sudden coming would not cause terror, but be endurable by a mind prepared in advance. …

On the Gospel of Luke ↗

Bonaventure

Second, with regard to the exhortation of the disciples to the understanding of truth, there is added: While all were marveling at all the things that he was doing and also saying and speaking; he said to his disciples: Place these words in your hearts; as if he were saying to them: while others recognize and admire the greatness of the miracles, you consider the humility of the future reproaches and "store away in your mind the outcome of the precious blood by which the world is to be redeemed, while the rest marvel only at the …

Commentary on Luke, Chapter 9 ↗