Writings of Baal HaSulam, “The Arvut”(Mutual Guarantee): The work in Torah and Mitzvot is expressed in the words, “and ye shall be unto Me a kingdom of priests.” A kingdom of priests means that all of you, from youngest to oldest, will be like priests….so will the entire nation be organized so that the whole earth and everything in it will be dedicated to the Creator only.
It turns out that he who harvests his field in order to feed his fellow person is the same as he who sacrifices to the Creator. Moreover, it seems that the Mitzva, “Love thy friend as thyself,” is more important than he who makes the sacrifice….
The closer a person’s actions are to serving the physical needs of others, the higher his work is. If I have stitched sandals for a friend with loyalty and love, like Rabbi Yochanan, the Shoemaker, then with this I have done work that is greater and more important than the work that the High Priest does in the Temple in the Holy of Holies on the Yom Kippur (Day of Judgment).
All the more so, if I go out of my way, out of my surroundings to the wider public in order to explain to a person the goal of creation and to attract him to it, to give him a little knowledge about it, to give him support, to lend a helping hand, then there is no more important work than this. It is even impossible to compare how important this work is compared to all other work.
From the 5th part of the Daily Kabbalah Lesson 6/18/14, Writings of Baal HaSulam