And he said means, of course, that “The LORD said” (Good News Translation). My presence will go with you is literally “my face will go.” With you [singular] is implied from the second clause. The word for “face” is always used in the plural, even when the singular is meant, and so the verb is also plural. Here, as elsewhere, it represents Yahweh’s presence. This simply means “I will go with you” (Good News Translation), but it is probably better to bring out the emphasis suggested by the context, “I myself shall go with you” (New Jerusalem Bible).

And I will give you rest is literally “and I will cause rest to [or, for] you.” It is not entirely clear what this expression means. The you is singular, so it is best to understand this as a promise only to Moses. The promise does not yet include the people. (See verses 15-16.) Therefore Revised English Bible has “I shall go myself and set your mind at rest,” Durham has “Thus will I dispel your anxiety,” and New Jewish Publication Society’s Tanakh has “I … will lighten your burden.” These seem closer to the intended meaning than Good News Translation‘s “and I will give you victory.” Most translations are literal here, leaving it to the reader to decide what is intended. Having said all this, a phrase such as give you rest or “let you have peace” will probably fit the context.

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 .