"And he had a dream and behold, a ladder." From here our Sages of Blessed Memory said: There is no dream without an interpretation. This ladder is Sinai in numerical value (gematria). Another interpretation: A symbol of God.
Another interpretation: The ladder/stairway is the ramp of the altar. "Set on the ground." As it is stated, "At the foot of the mountain." (Exodus 19:7) "And its head reaching the heavens." As it is stated, "And the mountain was ablaze with flames to the very skies." (Deuteronomy 4:11) "And behold, messengers of God."
These are Moses and Aaron. Another interpretation: "Going up and going down on it." They go down and go up as he asks? Rather, these angels that went with him in the land of Israel do not go with him to outside of the land, but instead they go up.
And others went down with him to outside of Israel. And at the moment that they went up into heaven and saw the image of Jacob, our father, inscribed on the Throne of Glory, they said: Isn't he down below? Then who brought him here?! They went down and saw him and wanted to injure him, so immediately the Holy One Blessed Be God came down to save him.
This is the meaning of what is written, "And standing beside him was God." (Genesis 28:13) From here we learn that the pious ones are first and He rides upon them, as it is stated, God was gone from Abraham." (Genesis 17:22)