Charles Ellicott Commentary Matthew 19:20

"The young man saith unto him, All these things have I observed: what lack I yet?" — Matthew 19:20 (ASV)

All these things have I kept — There is obviously a tone of impatient surprise in the questioner’s reply. He had come seeking some great thing to satisfy his lofty aspirations for eternal life. He finds himself retaught the lessons of childhood, sent back, as it were, to a lower form in the school of holiness. He had not learned that to keep any one of those commandments in its completeness is the task of a lifetime, and that to keep one perfectly implies keeping all. In marked contrast with this half-contemptuous treatment of the simpler elements of religion, we may recall our Lord’s use of Scripture in the Temptation. He used three passages connected, directly or indirectly, with those written on the phylacteries that men wore, which would naturally be taught to children as their first lesson in the Law (see notes on Matthew 4:1-11).

What lack I yet? — Ignorant as the young ruler was of his own spiritual state, his condition was not that of the self-satisfied Pharisee. The question implied a dissatisfaction with himself, a sense of incompleteness, and a hunger and thirst for a higher righteousness. This accounts for the way in which our Lord dealt with him.