“Yahweh said to Moses, ‘Go leave this place, you and the people whom you have brought up out of the land of Egypt.  Go to the land of which I swore to Abraham, Isaac, and Jacob, saying, to your descendants I will give it. I will send an angel before you.  I will drive out the Canaanites, the Amorites, the Hittites, the Perizzites, the Hivites, and the Jebusites.   Go up to a land flowing with milk and honey.  But I will not go up among you, or I would consume you on the way, for you are a stiff-necked people.’”

Yahweh told Moses to leave this place.  He wanted them to go to a land flowing with milk and honey that he promised to Abraham, Isaac, and Jacob because he was going to destroy the inhabitants there.  However, he was not going to be among them because he might consume these stiff-necked people.

“When the people heard these harsh words, they mourned.  No one put on ornaments.  Yahweh had said to Moses, ‘Say to the Israelites, `You are a stiff-necked people.  If for a single moment I should go up among you, I would consume you. So now take off your ornaments, and I will decide what to do with you.’ Therefore the Israelites stripped themselves of their ornaments from Mount Horeb onward.”

The Israelites mourned when they heard the harsh words of Yahweh.  They took off their ornaments from Mount Horeb onward.  It is not called Sinai but Horeb