So they took ashes refers to both Moses and Aaron. For ashes see the discussion at verse 8. From the kiln is omitted in Good News Translation as unnecessary repetition. The kiln, with the definite article, does not refer to a specific furnace, so “a kiln” is better (Translator’s Old Testament). And stood before Pharaoh may be rendered as “appeared before Pharaoh” (New Jewish Publication Society’s Tanakh) or “came into Pharaoh’s presence” (Translator’s Old Testament).

Moses alone threw the ashes, not Aaron, as Yahweh had commanded. Threw them really means “scattered them” or “tossed them” (New American Bible, New English Bible). The plural pronoun them, of course, refers to the ashes. If a singular noun like “soot” is used, the singular pronoun will be necessary. (See the comment on the collective noun at verse 8.) The direction was toward heaven, so one may say that Moses “threw them into the air” (Good News Translation). This action suggests that the wind then carried the “fine dust” all over Egypt. For and it became boils …, see verse 9.

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 .