Exodus 34:28-30

Young's Literal Translation

²⁸ And he is there with Jehovah forty days and forty nights; bread he hath not eaten, and water he hath not drunk; and he writeth on the tables the matters of the covenant -- the ten matters.

²⁹ And it cometh to pass, when Moses is coming down from mount Sinai (and the two tables of the testimony [are] in the hand of Moses in his coming down from the mount), that Moses hath not known that the skin of his face hath shone in His speaking with him,

³⁰ and Aaron seeth -- all the sons of Israel also -- Moses, and lo, the skin of his face hath shone, and they are afraid of coming nigh unto him.