(21) From my youth up.--The detail may be noted as a point in common with St. Mark, as also is the omission of the question, "What lack I yet?" given in St. Matthew.
Verse 21. - And he said, All these have I kept from my youth up. He listens to the Master with something like impatient surprise. There is a ring of concealed indignation in his "All these have I ever kept. What do you take me for? I am a religious, God-fearing Jew; from my child-days have I kept these." Kept these! How little the poor questioner knew the secrets of his Own heart! Yet he had answered Jesus in the true spirit of a Pharisee trained carefully in the rabbinic schools. We read, for instance, in the Talmud how "when Rabbi Chaninah was dying, he said to the angel of death, 'Go and fetch me the book of the Law, and see whether there is anything in it which I have not kept.'"
18:18-30 Many have a great deal in them very commendable, yet perish for lack of some one thing; so this ruler could not bear Christ's terms, which would part between him and his estate. Many who are loth to leave Christ, yet do leave him. After a long struggle between their convictions and their corruptions, their corruptions carry the day. They are very sorry that they cannot serve both; but if one must be quitted, it shall be their God, not their wordly gain. Their boasted obedience will be found mere outside show; the love of the world in some form or other lies at the root. Men are apt to speak too much of what they have left and lost, of what they have done and suffered for Christ, as Peter did. But we should rather be ashamed that there has been any regret or difficulty in doing it.
all these have I kept from my youth up; See Gill on Matthew 19:20 where it is added, what lack I yet?