Jesus stopped on the man's first words, "Good Master," and asked him to think about what he was saying. Barnes paraphrases the question this way: "Why do you give to me a title that belongs only to God?" He says Jesus was not denying His divinity, but correcting "a foolish habit of compliment and flattery." Gill puts the weight elsewhere: Jesus said this "not as denying that he was good," but "to lead this young man to a true knowledge of him, and his goodness, and even of his proper deity." Either way, the question presses the man to ask who Jesus really is, and what "good" really means.

Jesus answered His own question at once: "there is none good but one, that is, God" (Mark 10:18). Then He pointed the man to God's commandments (Mark 10:19). The man answered, "Master, all these have I observed from my youth" (Mark 10:20). Notice that this time he says only "Master," not "Good Master."

Barnes explains that "good" was probably a title Jews were in the habit of giving to their religious teachers, and "Master" means teacher. Calling a teacher "good" could be polite flattery more than real thought.

All three Gospels record this question in the KJV with the same words, "Why callest thou me good?" (Matthew 19:17; Luke 18:19). Gill adds that "there is none good but one, that is, God" is a statement of the unity of God, not meant to exclude the Son and the Spirit.

This question is about God's goodness. Jesus set the bar where it belongs: only God is good. That one sentence quietly undoes the man's hope of being good enough to earn eternal life, and Barnes gives as one probable reason for Jesus' next words that He wanted to test the man, "to show him his need of a Saviour."

The question also invites the man to see who is standing in front of him. If only God is good, and he has just called Jesus good, what does that mean? Gill reads the question as Jesus leading him toward a true knowledge of Himself. Jesus did not explain it all. He asked, and left the man to think.