You see, in present day society, money talks. It gives you opportunities, gets you places, and opens doors that would otherwise be closed.
However, there is one door that no amount of money can open: the gate to heaven.
The young ruler learns of this when Jesus told him to give his wealth to the poor in order to inherit eternal wealth in heaven. Jesus also commands the young man to follow him.
This presented a problem for the ruler. Should he give up his earthly treasures and follow this man? At this point, his possessions had become an idol to him that he wanted to hold on to more than the Lord. It became an obstacle in his spiritual journey with God.
The young man walks away downcast because he can't bear to give up his riches. He is the only person in the New Testament that we know of who comes to Jesus and leaves saddened.
A practical analogy for this situation would be a doctor diagnosing a patient's problem, and then the patient leaving unhappily because they don't want to do what the doctor tells them to in order to become healthy.
The rich young ruler was supposed to give up his wealth so that he could follow the Lord without distractions, just as we're called to give up anything that we put before Him. Following Christ is the only way to inherit eternal life; salvation from beginning to end is not something a human can achieve by their own strength.
Life Lesson: Put away your idols so that you may be in the presence of the Lord.