They were speaking
Of his departure
Jesus was to accomplish this
οἳ ὀφθέντες ἐν δόξῃ ἔλεγον τὴν ἔξοδον αὐτοῦ, ἣν ἤμελλεν πληροῦν ἐν Ἱερουσαλήμ
Luke said that the 3 men, Jesus, Moses, and Elijah, all appeared in their glory (οἳ ὀφθέντες ἐν δόξῃ). They were speaking about the departure of Jesus (ἔλεγον τὴν ἔξοδον αὐτοῦ) and how it was about to be accomplished (ἣν ἤμελλεν πληροῦν) in Jerusalem (ἐν Ἱερουσαλήμ). This is a unique statement by Luke, since the other synoptics did not mention this. Luke said that these 3 transfigured men, Moses, Elijah, and Jesus, talked about the future departure of Jesus from Jerusalem, in other words, his upcoming death. Have you ever discussed your future death with anyone?
“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
“When Pharaoh let the people go, God did not lead them by way of the land of the Philistines, although that was near. God thought, ‘If the people face war, they may change their minds and return to Egypt.’ So God led the people by the roundabout way of the wilderness toward the Red Sea. The Israelites went up out of the land of Egypt prepared for battle. Moses took with him the bones of Joseph who had required a solemn oath of the Israelites, saying, ‘God will surely take notice of you, and then you must carry my bones with you from here.’”
Instead of going the short route through the Philistines, where they might have to face a war, Yahweh led them into the wilderness toward the Red Sea. The Israelites were prepared for a battle against the Egyptians. Moses took with him the bones of Joseph.
“They set out from Succoth, and camped at Etham, on the edge of the wilderness. Yahweh went in front of them in a pillar of cloud by day, to lead them along the way, and in a pillar of fire by night, to give them light, so that they might travel by day and night. Neither the pillar of cloud by day nor the pillar of fire by night left its place in front of the people.”
So they left Succoth, and camped at Etham, on the edge of the wilderness, near the Red Sea. Yahweh went in front of them in a pillar of cloud during the day and in a pillar of fire at night. Fire and clouds were normal ways of expressing God’s presence and guidance.