This verse begins a new paragraph in some translations, but it actually concludes the section. Then the people of Israel is changed to “Then they” in Good News Translation and Contemporary English Version, referring to “the people” in verse 27. But if “the people” in verse 27 is understood to refer to “all the elders” in verse 21, which is more likely, then here it means “the Israelites” as in New Revised Standard Version. Went and did so refers to one action instead of two. So New International Version has “The Israelites did just as the LORD commanded…,” and Translator’s Old Testament has “… did exactly as the LORD had commanded….” (But see New Jerusalem Bible, “went away and did,” and Durham, “dispersed and did.”) The word so is not necessary if the two clauses are combined.

The following clause concludes with the words so they did, which only emphasizes the clause as the LORD had commanded. This emphasis may be expressed in a single clause by adding “exactly as” (Revised English Bible) or “just as the LORD had commanded” (New Revised Standard Version). Aaron has not been mentioned since verse 1, so Moses and Aaron is probably an editorial conclusion to the instructional material of 12.1-28. (See the introductory remarks at the beginning of the chapter.)

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 .