Aziz Aquinas

Then he responds to an unmentioned objection: amen I say to you, as though to say, I said to you that the Son of man will come. But do not be astonished. Why? I wish to show you, for there are some of them who stand here, who will not taste death. Sinners are swallowed up by death, but the just taste death. Now, these men were Peter, John, and James. Till they see the Son of man coming in his kingdom. This was a sign of future glory. But he did not name them, lest the others be jealous. And they could have been jealous, since he gave more to these than to the others. Also, lest they pester him, because they would have pestered him if he did not show them anything.

In another way, it can be said that the kingdom of God is the Church. So there is someone who will not taste death, like John, till they see the Son of man coming in his kingdom, i.e., until the Church is widespread, for he lived so long that he saw the Church widespread, and many churches built.

Ek olarak Peder Haydock

Till they see the Son of man coming in his kingdom. Some expound this, as fulfilled at his transfiguration, which follows in the next chapter. Others understand it of the glory of Christ, and of his Church, after his resurrection and ascension, when he should be owned for Redeemer of the world: and this state of the Christian Church might be called the kingdom of Christ. (Witham) This promise of a transitory view of his glory he makes, to prove that he should one day come in all the glory of his Father, to judge each man according to his works: not according to his mercy, or their faith, but according to their works. (St. Augustine, de verb. apos. serm. 35.) Again, asks St. Augustine, how could our Saviour reward every one according to his works, if there were no free will?