Charles Ellicott Commentary Exodus 33:21

"and Jehovah said, Behold, there is a place by me, and thou shalt stand upon the rock:" — Exodus 33:21 (ASV)

There is a place by me. — A place on the summit of Sinai, where God had been manifesting Himself, is clearly intended; but it is impossible to fix the place with any certainty. Speculations like those of Dr. Robinson (Biblical Researches, Vol. 1, p. 153) are of little value.