Where the Non-Canonical Gospel Held in Common By Clement and the Carpocrates Certainly Placed the Agrapha 'You Have Heard that the Law Commanded, Thou Shalt Not Commit Adultery. But I Say, Thou Shalt Not Lust'

And a certain ruler asked him, saying, "Good Teacher, what shall I do to inherit eternal life? I know the commandments - Do not commit adultery, Do not kill, Do not steal, Do not bear false witness, Honour thy father and thy mother. All these have I have observed from my youth up." But Jesus said "You have heard that the law commanded, Thou shalt not commit adultery. But I say, Thou shalt not lust, If you will be perfect, sell all your possessions, and distribute unto the poor, and thou shalt have treasure in heaven: and come, follow me."  And when he heard these things, he became exceeding sorrowful: for he was very rich.

This reconstruction of course is based on the assumption that the gospel was one and the same with the Marcionite gospel which is supported by the various references to the saying cited in the posts below.