The blood refers to the animal’s “blood on the doorposts” in verse 7. Another way to express this is “The animal blood that you smear on the doorposts of your houses.” Shall be a sign is the same word (ʾoth) used for the “signs and wonders” performed by Moses and Aaron in 7.3 and the plagues brought on by Yahweh. But here it carries the meaning of a distinguishing mark. (See the comment on “wonders” at 3.20.) So New American Bible has “the blood will mark the houses where you are” (similarly Jerusalem Bible). One may also translate as Contemporary English Version does, “will show me where you live.” A sign for you may seem strange, for it was to be a distinguishing mark for Yahweh to see. Good News Translation omits for you (as do New American Bible, Jerusalem Bible), but Revised English Bible uses it to begin the verse: “As for you, the blood will be a sign.” Durham interprets this to mean “for your benefit” and translates “The blood is to be for your protection.” It is recommended that translators follow Good News Translation.

Upon the houses where you are may not mean “in which you live,” for verse 4 suggests that some of the smaller families would be moving in with others to share in the meal, and verse 7 specifies that the blood is to be smeared on the houses where the people are to eat. New Jewish Publication Society’s Tanakh has “the houses where you are staying.” An alternative translation model for the first part of this verse is “The animal blood that you smear on the doorposts of your houses will show me where you are staying.”

And when I see the blood is literally “and I will see the blood.” In languages where the same word is used for “when” and “if,” one should guard against suggesting that Yahweh might overlook some houses. An alternative model is “I will see the blood and will pass over….” I will pass over you uses the verb pasach, which is similar to pesach (“passover”) in verse 11. The obvious play on words is difficult to bring out in translation, so a footnote may be helpful to the reader. (For a fuller discussion see verse 27 and the introduction to this section, 12.1-14.)

And no plague uses the word meaning “blow” or “affliction.” It does not indicate the nature of the blow or the kind of affliction. But the following words, shall fall upon you to destroy you, suggest a “destructive blow” (New American Bible). The basic meaning of destroy is to ruin or wipe out. (See verse 23.) Revised English Bible translates this as “the mortal blow will not touch you,” while Good News Translation simply has “I … will not harm you.” When I smite the land of Egypt uses the same verb as in verse 12, meaning to strike or hit. Good News Translation summarizes with “when I punish the Egyptians.” One may also translate this as “I … will not harm you when I punish the Egyptians with terrible plagues” or “I … will not harm you when I use terrible plagues to punish the Egyptians.” Or one may restructure the final part of this verse in a similar way to Contemporary English Version and say “Then you won’t be bothered by any of the terrible plagues I will bring on Egypt.” However, in languages that do not use the passive voice, it is possible to express this as “Then I [Yahweh] will not cause you harm when I severely punish the Egyptians,” or even “I will punish the Egyptians with terrible plagues, but I won’t harm you.”

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 .