Every one of the six hundred and thirteen precepts serves to inculcate some truth, to remove some erroneous opinion, to establish proper relations in society, to diminish evil, to train in good manners, or to warn against bad habits. All this depends on three things: opinions, morals, and social conduct.... these three principles suffice for assigning a reason for every one of the Divine commandments.

Ch.31 - Guide for the Perplexed (c. 1190) - Part III