DEAR REV. GRAHAM: How do you know God gave the Ten Commandments to Moses? Maybe Moses just made them up when he went up on that mountain, and they didn't really come from God after all. —P.H.
Dear P.H.: No one at the time doubted that God had given the Ten Commandments to His people, or thought they were something Moses dreamed up. The dramatic thunder and lightning that accompanied Moses' journey up Mt. Sinai reinforced their conviction that God was speaking to him (see Exodus 20:18). Jesus repeatedly taught that these commandments came from God, not man.
I can't help but wonder, however, why you're asking this question. Could it be that you secretly hope God didn't give the Ten Commandments to us — and therefore you can ignore them and live any way you want to? If so, I urge you to stop and reconsider where this leads you. You may think it leads to freedom and happiness — but some day you'll discover this is a lie, for it only leads to discontent and hopelessness.