When the Savior invited this young man to turn from his great possessions, give them to the poor and come follow him... he was asking him to put his heart where his mouth was. With God... it is all about the heart! On so many levels, this young man got it! He kept the commandments... he recognized the Savior... he knelt in humility at His feet. He was doing so many of the right things... but his inability to receive the Savior's invitation... indicated that he had yet to experience the mighty change of heart.
For where your treasure is, there will your heart be also.
3Nephi 13:21
A disciple is a learner of a discipline. As disciples of Christ we strive to learn His discipline, to model and pattern our lives... and in turn our hearts... after His. The very essence of who He is, is Love. It is the great motivator for everything He has ever done or will ever do. Charity is the pure love of Christ. Charity is the ultimate evidence of the converted heart.
Beloved, let us love one another: for love is of God;
and every one that loveth is born of God, and knoweth God.
1 John 4:7
The person who is solely focused on "doing" the right things, rather than on "becoming" as He is... misses the "weightier matters of the law" and the entire point of this life.
Though I speak with the tongues of men and of angels, and have not charity, I am become as sounding brass, or a tinkling cymbal.And now abideth faith, hope and charity, these three; but the greatest of these is charity.
1Corinthians 13:1, 13
In the end, who or what we love is all that will really matter.
But charity is the pure love of Christ, and it endureth forever and
whoso is found possessed of it at the last day, it shall be well with him.
Wherefore, my beloved brethren, pray unto the Father with all the energy of heart, that ye may be filled with this love, which he hath bestowed upon all who are true followers of his Son, Jesus Christ, that ye may become the sons of God; that when he shall appear we shall be like him...
Moroni 7:47-48
whoso is found possessed of it at the last day, it shall be well with him.
Wherefore, my beloved brethren, pray unto the Father with all the energy of heart, that ye may be filled with this love, which he hath bestowed upon all who are true followers of his Son, Jesus Christ, that ye may become the sons of God; that when he shall appear we shall be like him...
Moroni 7:47-48