Matthew 22:34

Jesus had put the Sadducees to silence, to show that the tongue of falsehood is silenced by the brightness of truth. For as it belongs to the righteous man to be silent when it is good to be silent, and to speak when it is good to speak, and not to hold his) peace; so it belongs to every teacher of a the Not indeed to be silent, but to be silent as far as any good purpose is concerned.

For in this law given to Adam we recognise in embryo all the precepts which afterwards sprouted forth when given through Moses; that is, Thou shalt love the Lord thy God from thy whole heart and out of thy whole soul; Thou shalt love thy neighbour as thyself; Thou shalt not kill; Thou shall not commit adultery; Thou shalt not steal; False witness thou shall not utter; Honour thy father and mother; and, That which is another's, shall thou not covet.

(Verse 34 and following) But when the Pharisees heard that he had silenced the Sadducees, they gathered together. And one of them, a lawyer, asked him a question to test him: "Teacher, which is the great commandment in the Law?" What we read about Herod and Pontius Pilate, that they conspired in the death of the Lord, we also see now concerning the Pharisees and the Sadducees, who are opposed to each other, but agree with the same mind in testing Jesus. Therefore, those who had already been confuted in the display of the coin and had seen the faction of the opposing party undermined, should have been warned by example not to plot further snares: but malice and envy nourish audacity. One of the legal experts, not desiring to not know but attempting, asks whether the one being questioned knew what was being asked, what the greater commandment is: not asking about the commandments, but what the first and great commandment is; so that when all that God has commanded is great: whatever he may answer, he may have an opportunity to slander, asserting that something else is great among many. Therefore, whoever knows and asks not by desire to learn, but by the desire to know, whether the one who is going to respond knows, approaches in the likeness of the Pharisees, not as a disciple, but as a tempter.

Or the Pharisees meet together, that their numbers may silence Him whom their reasonings could not confute; thus, while they array numbers against Him, showing that truth failed them; they said among themselves, Let one speak for all, and all speak, through one, so if He prevail, the victory may seem to belong to all; if He be overthrown, the defeat may rest with Him alone; so it follows, Then one of them, a teacher of the Law, asked him a question, tempting him.

After the humiliation of the Sadducees Jesus was highly regarded by the crowds. The Pharisees, filled with envy out of an immeasurable shamelessness, again were testing him, hypocritically asking if he might deliver a ruling concerning the first commandment. By doing so, perhaps Jesus would amend the commandment in a manner that might lead to an accusation against him. Now, Matthew and Luke call the person who asked the question a lawyer, while Mark calls him a teacher of the law. This does not indicate a disagreement. For they both represent the questioner as one learned in the law and as a teacher of the law who is an interpreter of the law to the people. But the Lord publicly reveals their evil. They were not coming to have him interpret the law so that they might benefit but because they were seized by envy. So Jesus teaches that one should not measure out one's devotion, loving God in part but also clinging in part to the concerns of this world. Through his teaching Jesus said that his commandment was the summary of all the commandments. The lawyer thought he could cast Jesus into danger as one who makes himself out to be God. Jesus failed to respond in the manner he expected, but he ends up praising Jesus, as Mark says.