The LORD will fight for you reflects the ancient Israelite concept of “holy war,” in which Yahweh is the divine warrior who defeats Israel’s enemies with supernatural power. (See 15.3.) New Jerusalem Bible says it well: “Yahweh will do the fighting for you.”

And you have only to be still is ambiguous. The verb may be understood either as being silent or as doing nothing. Good News Translation chooses the former, “and all you have to do is keep still,” but Contemporary English Version chooses the latter, “and you won’t have to do a thing.” (The problem is discussed in verse 15.) New English Bible has “so hold your peace,” but Revised English Bible has changed it to “so say no more.” In keeping with the holy war concept, however, it is better to follow the idea of the people doing nothing and simply letting Yahweh do the fighting for them.

Alternative translation models for this verse are:

• Yahweh will fight your enemies for you. So all you have to do is keep quiet.

• Yahweh will fight your enemies for you. So you will not have to do anything.

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 .