Jesus saw past the flattery. Luke says He "perceived their craftiness," and His question names what they were doing: testing Him, hoping He would stumble. Gill describes Him as "Knowing what was in them, and being a discerner of the thoughts and intents of their hearts." Barnes, on the same words in Matthew 22:18, explains "tempt ye me" as "Try me, or endeavor to lead me into difficulty by an insidious question." Before He answered their question, Jesus let them know He saw their purpose.

The spies give no reply to this question. Jesus goes straight on: "Shew me a penny. Whose image and superscription hath it?" (Luke 20:24). After they answer "Caesar's" and hear Him say, "Render therefore unto Caesar the things which be Caesar's, and unto God the things which be God's," Luke records that "they could not take hold of his words before the people: and they marvelled at his answer, and held their peace" (Luke 20:25-26).

The word "craftiness" is the Greek panourgia, which Thayer defines as "craftiness, cunning." Paul uses the same word for the serpent who "beguiled Eve through his subtilty" (2 Corinthians 11:3). The verb "tempt" (peirazo) means to test or make trial of someone.

The question "Why tempt ye me?" is in the Textus Receptus (the Greek text behind the KJV) but is not in the critical Greek editions used by modern translations, so the ESV of Luke 20:23 ends with "and said to them," and goes on to "Show me a denarius" (Luke 20:24). The same question does appear in both the KJV and ESV of the parallel accounts (Matthew 22:18; Mark 12:15).

This question shows that Jesus knows the heart. The spies came dressed as "just men" (Luke 20:20) and opened with praise (Luke 20:21), but He saw what they were really doing. Matthew Henry's Concise Commentary says, "Those who are most crafty in their designs against Christ and his gospel, cannot hide them."

Yet Jesus did not walk away. He exposed their motive and still gave them a true answer, one that taught everyone listening what is owed to Caesar and what is owed to God (Luke 20:25). His knowledge of their hearts did not make Him less truthful with them.