Could not find - Were not able to accomplish their purpose; they did not know "how" to bring it about.
Very attentive - literally, "hung upon him" to hear him. The word denotes an anxious desire, a fixed attention, a cleaving to him, and an unwillingness to "leave" him, so that they might hear his words. This is always the case when people become anxious about their salvation. They manifest it by hanging on the preaching of the gospel; by fixed attention; and by an unwillingness to leave the place where the word of God is preached. In view of the fact that the Lord Jesus wept over Jerusalem, we may remark:
(1) It was on account of the sins and danger of the inhabitants, and of the fact that they had rejected offered mercy.
(2) there was "occasion" for weeping. Jesus would not have wept had there been no cause for it. If they were in no danger, if there was no punishment in the future world, why should he have wept? When the Lord Jesus weeps over sinners, it is the fullest proof that they are in danger.
(3) sinners are in the same danger now. They reject Christ as sinners did then. They despise the gospel as they did then. They refuse now to come to him as the inhabitants of Jerusalem did. Why are they not then in the same danger?
(4) deep feeling, gushing emotions, lively affections, are proper in religion. If the Saviour wept, it is not improper for us to weep - it is right. Nay, can it be right "not" to weep over the condition of lost man.
(5) Religion is tenderness and love. It led the Saviour to weep, and it teaches us to sympathize and to feel deeply. Sin hardens the heart, and makes it insensible to every pure and noble emotion; but religion teaches us to feel "for others' woes," and to sympathize in the danger of others.
(6) Christians and Christian ministers should weep over lost sinners. They have souls just as precious as they had then; they are in the same danger; they are going to the judgment-bar; they are wholly insensible to their danger and their duty.
"Did Christ o'er sinners weep?
And shall our cheeks be dry?
Let floods of penitential grief.
Burst forth from every eye.
"The Son of God in tears.
Angels with wonder see!
Be thou astonished, O my soul;
He shed those tears for thee.
"He wept that we might weep;
Each sin demands a tear:
In heaven alone no sin is found.
And there's no weeping there."

Were very attentive to hear him - Or, They heard him with the utmost attention, εξεκρεματο αυτου ακουων, literally, They hung upon him, hearing. The same form of speech is used often by both Greek and Latin writers of the best repute. -
Ex vultu dicentis, pendet omnium vultus.
The face of every man hung on the face of the speaker.
- Pendetque iterum narrantis ab ore.
Virg. Aen. iv. 79
And she hung again on the lips of the narrator.
The words of the evangelist mark, not only the deepest attention because of the importance of the subject, but also the very high gratification which the hearers had from the discourse. Those who read or hear the words of Christ, in this way, must inevitably become wise to salvation.
The reader is requested to refer to Matthew 24 (note), and to Matthew 25:14 (note), for more extensive information on the different subjects in this chapter, and to the other parallel places. The prophecy relative to the destruction of Jerusalem is one of the most circumstantial, and the most literally fulfilled, of any prediction ever delivered. See this particularly remarked at the conclusion of Matthew 24 (note), where the whole subject is amply reviewed.

And could not find what they might do,.... The Vulgate Latin, Syriac, and Ethiopic versions, and so Beza's most ancient copy, add, "to him"; they could not find an opportunity of seizing him, nor any advantage against him; they knew not what steps to take, nor how to bring about their wicked design of destroying him.
For all the people were very attentive to hear him; there were great crowds always about him, that hung upon him, as the word rendered "attentive" signifies; they heard him with great eagerness and diligence, and were ready to catch every word that dropped from his lips; and were exceedingly taken with him, having never heard any man speak like him: wherefore having so many followers, and being so high in the opinion and affection of the people, the sanhedrim were at a loss what method to make use of to gain their point; and they feared the people, should they seize him publicly, lest they should rise and rescue him, and cause a tumult and disturbance.

were very attentive to hear him--hung upon His words.