Theophylact of Ohrid

At this they should have been terrified, but after such words they became even more enraged and in their frenzy ask: "Are You then the Son of God?" He, with moderation and pointing out the absurdity of their question, answers them: "You say that I am," for He despised their fury and spoke to them fearlessly.

Commentary on Luke ↗

Ambrose of Milan

The Lord had rather prove Himself a King than call Himself one, that they might have no excuse for condemning Him, when they confess the truth of that which they lay against Him. It follows, And he said, Ye say that I am.

Catena Aurea by Aquinas ↗

Bede

And they all said: Are you then the Son of God? You say that I am. Thus he tempers his response, so that he both speaks the truth, and his statement provides no opportunity for calumny. For he preferred to prove himself the Christ, the Son of God, rather than to say it, so that he would be taken up for condemnation by those who acknowledge what they themselves propose.

On the Gospel of Luke ↗

Bonaventure

Third, as to the malice in replying, it is added: And they all said: Are you then the Son of God? They as it were draw a conclusion and seek a charge, so that, if he should assert this, they might condemn him as a blasphemer, according to that passage in John 5: The Jews persecuted Jesus, "not only because he broke the Sabbath," but also because "he called God his Father, making himself equal to God." Since therefore they were here concluding what was true, and yet regarded it as evidently false, therefore Christ neither entirely …

Commentary on Luke, Chapter 22 ↗