Quoted from Genesis / Bereshit 28

Jacob and his stoneHe came to a familiar place and spent the night there because the sun had already set. Taking some stones, he placed them at his head and lay down to sleep there.

He had a vision in a dream. A ladder was standing on the ground, and its top reached up toward heaven. God's angels were going up and down on it. Suddenly he saw God standing over him.

[God] said, 'I am God, Lord of Abraham your father, and Lord of Isaac. I will give to you and your descendants the land [stones] upon which you are lying.

Your descendants will be like the dust of the earth. You shall spread out to the west, to the east, to the north, and to the south. All the families on earth will be blessed through you and your descendants.

I am with you. I will protect you wherever you go and bring you back to this soil. I will not turn aside from you until I have fully kept this promise to you.'

Jacob awoke from his sleep. 'God is truly in this place,' he said, 'but I did not know it.'

He was frightened. 'How awe-inspiring this place is!' he exclaimed. 'It must be God's temple. It is the gate to heaven!'

Jacob got up early in the morning and took the stone that he had placed under his head. He stood it up as a pillar and poured oil on top of it.

He named the place God's Temple [Beth El: Literally, "House of God"]. The town's original name, however, had been Luz [Hebrew: almond TREE: the levels of the ladder are the Tree of Life: Kabbalah].

yesodThe Zohar says that the ladder that Jacob (Yaacov) saw in his dream represents the sephirah Yesod [Hebrew: foundation; related to the sexual organs], which is the energetic conduit that connects man with heaven. [Zohar, Bereshit 149]

And in this verse: “And he was afraid, and he said, How awesome is this place; this is none other than the House of G-d, and this is the gate of heaven.” (Bereshit, 28:17) Jacob was secretly referring to "the place of the Brit" (the sexual organs). Regarding the verse, “And he lied down (v’yishkav) in that place,” (Bereshit, 28:11) some Rabbim teach that v’yishkavcan be read, v’ yeish kaf bet– the place of the Brit (sexual organs).