If the family of Egypt go not up. Egypt is mentioned as the great typical enemy of God and Israel, and therefore most obnoxious to punishment if it did not obey the call. That have no rain. This rendering implies, what is not the fact, that Egypt is without rain, and is not dependent upon rain for its fertility.
The expression in the text is elliptical, being merely, "then not on them," and it is obviously natural to supply, "shall there be rain." As the rise of the Nile depends upon the equinoctial rains in the interior, the failure of these would be disastrous.
Another way of rendering the passage is to combine the clauses and append a note of interrogation; thus: "Shall there not be upon them the plague wherewith," etc.? The LXX. and Syriac omit the negative, καὶ ἐπὶ τούτους ἔσται ἡ πτῶσις, "Even upon these shall be the plague."