And be ready by the third day is literally “and they to be standing firm for the third day.” This, of course, was “the day after tomorrow” (Good News Translation), counting the day this statement was spoken as the first day. For on the third day may be changed to “On that day” (Good News Translation) to avoid repeating the same words. For here means “because” (New Revised Standard Version). The LORD will come down upon Mount Sinai, literally “will descend upon,” implies that Yahweh is speaking from a place above the mountain. These are Yahweh’s words, so the pronoun may be changed as in Good News Translation, “I will come down.” Contemporary English Version combines the two clauses as follows: “and be ready by the day after tomorrow, when I will come down to Mount Sinai.” Note that the use of “from Mount Sinai” will not be accurate, and it is not supported by the context (see verse 18); upon or “on” is the more probable meaning of the preposition in this instance.

In the sight of all the people is literally “to the eyes of all the people.” Good News Translation‘s “where all the people can see me” suggests that they will not see Yahweh while he is descending, but only after he will come down. Such an interpretation is possible, but most translations suggest that Yahweh will descend “while all the people are watching” (Translator’s Old Testament).

Quoted with permission from Osborn, Noel D. and Hatton, Howard A. A Handbook on Exodus. (UBS Helps for Translators). New York: UBS, 1999. For this and other handbooks for translators see here .