The young man believed he had done everything on the list, yet he sensed something was still missing. That is why he asked. Barnes puts his claim in plain words: "I have made them the rule of my life." He then wondered whether the Messiah taught some further command he still needed to obey to be saved. Gill thinks the man was sincere as far as outward conduct went: "nor could he charge himself with any open and flagrant transgression of them; not understanding the internal sense, extensive compass, and spirituality of them." His question is honest, and it opens the door for Jesus to show him what he could not see.

Jesus answered him directly: "If thou wilt be perfect, go and sell that thou hast, and give to the poor, and thou shalt have treasure in heaven: and come and follow me" (Matthew 19:21). The young man had asked what he lacked, and Jesus showed him. "But when the young man heard that saying, he went away sorrowful: for he had great possessions" (Matthew 19:22). Mark adds that before Jesus spoke, "Jesus beholding him loved him" (Mark 10:21).

"Lack" translates hustero, which Thayer defines as to be behind, to fall short, or to be lacking. The young man knew he fell short of something, even while claiming to have kept the law.

Jesus' reply uses "perfect" (Matthew 19:21). Barnes says the word means "complete in all its parts," finished, "having no part wanting." So Jesus answers the man's question in his own terms: what you lack is what would make you complete. Barnes adds that Jesus gave this command to test his character and show him that he had not kept the law as he supposed. Gill says it was meant to discover "his sinful love of the world." Matthew and Mark both say he went away because "he had great possessions" (Matthew 19:22; Mark 10:22).

This is one of the most honest questions in the Gospels, and Jesus answered it honestly. The man's lack was not one more rule. It was a heart that held its riches more tightly than it held God. Jesus' answer was not only "sell," but "come and follow me." What the man lacked was Jesus Himself.

Matthew Henry observes, "Christ knew that covetousness was the sin which most easily beset this young man; though he had got honestly what he possessed, yet he could not cheerfully part with it." The disciples were astonished, and asked, "Who then can be saved?" Jesus answered, "With men this is impossible; but with God all things are possible" (Matthew 19:25-26). The man's question has a hopeful answer, but it is found in God, not in our own effort.