Exodus 18:15

And Moses said unto his father in law,.... In answer to his question; and there were two things, as Aben Ezra observes, he did to the people, and for which they came to him; the one is observed in this verse, and the other in the next:

because the people come unto me to inquire of God; of his mind and will in certain cases, and of his statutes and laws, as the following verse shows; what they should observe, and according to which they should conduct themselves: they came to inquire what God would have them to do; and, in doubtful cases, what was his will and pleasure, and to desire Moses to inform them; and if the things were of such a nature that he could not easily and readily do it, then to inquire of God for them, which in later times was done by Urim and Thummim.