R. Yossi says (Psalms 115:16) "the heavens are the heavens of the L–rd, etc." Moses and Eliyahu did not ascend above, and the glory did not descend below. But the L–rd said to Moses: I will call you from the top of the mountain, and you ascend, viz. (Exodus 19:20) "And the L–rd called Moses to the top of the mountain, and Moses ascended."
Rabbi Yosei Raised a Fundamental Question About the Boundary Between
Mekhilta Tractate Bachodesh 4:12