And if you make me an altar of stone provides an alternative to the “altar of earth” in verse 24. You is singular and stone is plural. You shall not build it uses a different word from make. The word for build means to erect or construct. Of hewn stones means stones that have been cut or shaped with a tool. New International Version and New Jerusalem Bible call them “dressed stones.” Good News Translation has “cut stones.” Contemporary English Version combines the phrase hewn stones with the following clause and says “do not use any tools to chisel the stones.”

For if is one word that has several meanings—for, if, because, when, or indeed. It must be translated according to the context. “Because” is probably the best rendering (so Good News Translation and Contemporary English Version). The rest of the sentence is literally “your chisel you move back and forth upon it and you will profane it.” “Chisel” (Good News Translation) is probably a better term, since it refers to the tool used by stone cutters. Wield suggests the continuous movement of the tool on the stone, but “use” (Good News Translation, Contemporary English Version) may be a more natural term. You profane means that you “defile” (New International Version) or “desecrate” (New American Bible) the stone. Good News Translation clarifies what this means: “you make them unfit for my use.” One may also say “You make the altar unfit for worshiping me.”

An alternative translation model for this verse is:

• If you use stones to build an altar, do not use any tools to chisel [or, cut] the stones. If you do that the altar will be unfit for worshiping me.

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 .