In Revised Standard Version this verse together with the preceding verse and the following verse comprise one long sentence. Good News Translation makes verses 20 and 21 one sentence, and then breaks verse 22 into two separate sentences. The translator will need to consider clarity and readability in determining how to structure these verses. It is possible to make verse 20 a complete sentence by itself. Verse 21 can then begin a new sentence, “He enjoined them….”
Enjoining is formal English and reflects the Hebrew, which expresses an obligation that is imposed on someone. The Hebrew word that is translated enjoining is a keyword in the ancient text of this part of chapter 9, where it occurs seven times (verses 21, 27, 29, three times in 31, and in 32). Thematically it parallels the author’s early insistence on the importance of the law, dat. New Jerusalem Bible here says “charging them to observe.” The Jews were directed by Mordecai to keep or “observe” these two days. In some languages this may be expressed as a third person command in indirect quotation; for instance, “he commanded them that they should keep the fourteenth and fifteenth days of the month of Adar as holidays year after year.”
The Revised Standard Version translation enjoining, that is, imposing an obligation on someone, represents the most widely accepted understanding of this verb form in this verse and is the understanding recommended in this Handbook. However, the verb in this form sometimes means “to confirm [or, to validate]” (see Psa 119.106; see also comments on Est 9.29, 31) rather than “to command.” It is possible to understand that Mordecai, by means of his letters, confirmed that the Jews should be celebrating these two days. Based on this understanding of the Hebrew verb, FOX says “[Mordecai wrote] to confirm upon themselves the celebration of the fourteenth day….” According to this interpretation Mordecai was not imposing something on the Jews; rather he was merely validating what the Jews had already decided to do. FOX translates this same verb “confirm” in 9.27, 29, 31, 32. If the language of the translation has a clear term for this kind of confirming, the translator may wish to use it; otherwise it seems preferable to translate it as imposing an obligation.
Quoted with permission from Omanson, Roger L. and Noss, Philip A. A Handbook on Esther (The Hebrew Text). (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .