Cyril of Alexandria

But the people held Christ in far higher estimation than the Scribes and Pharisees, and chiefs of the Jews, who not receiving the faith of Christ themselves, rebuked others. Hence it follows, And they could not find what they might do: for all the people were very attentire to hear him.

Catena Aurea by Aquinas ↗

Bede

For all the people were hanging on to hear him. This can be understood in two ways: either the people feared a tumult and did not find what they might do to Jesus whom they had determined to destroy; or they sought to destroy Jesus because, neglecting their teaching, they saw so many flock to hear him. Meanwhile, it is pleasing to consider briefly how beautifully the legal shadow of Passover corresponds, not only in mystery but also in the measure of time, with our true Passover in which Christ was sacrificed. …

On the Gospel of Luke ↗

Bonaventure

Third, as to the graciousness of Christ's teaching, by which it was pleasing to the devout, it is added: And they could not find what they might do to him, because he was accepted by the people. Whence below in chapter twenty: "The chief priests and scribes sought to lay hands on him, but they feared the people"; and this because they loved him as a faithful and good teacher. …

Commentary on Luke, Chapter 19 ↗