And the Jews undertook to do as they had begun, and as Mordecai had written unto them;

And the Jews undertook to observe with solemnity all they had begun to do at that time, which Mardochai by letters had commanded to be done.

And the Jews have received that which they had begun to do, and that which Mordecai hath written unto them,

And the Jews gave their word to go on as they had been doing and as Mordecai had given them orders in writing;

The Jews undertook to do as they had begun - They had already kept the fifteenth day, and some of them in the country the fourteenth also, as a day of rejoicing: Mordecai wrote to them to bind themselves and their successors, and all their proselytes, to celebrate this as an annual feast throughout all their generations; and this they undertook to do. And it has been observed among them, in all places of their dispersion, from that day to the present time, without any interruption.

And the Jews undertook to do as they had begun, and as Mordecai had written unto them. They engaged to keep these two days as festivals annually, as they had at this time done; not in a religious but in a civil way, not as parts of religious worship, and as additions to and innovations of the law, but by way of commemoration of a civil benefit which they had received; and yet we find in later times that this was scrupled by some as an innovation; for we are told (r) that there were eighty five elders, and more than thirty of them prophets, who were distressed about this matter, fearing it was an innovation.
(r) T. Hieros. Megillah. fol. 70. 4.

And the Jews undertook to do as they had begun, and as Mordochai had written to them. They had begun, as Esther 9:22 tells us, by keeping both days, and Mordochai wrote to them that they should make this an annual custom. This they agreed to do in consequence of Mordochai's letters. The reason of their so doing is given in Esther 9:24 and Esther 9:25, and the name of this festival is explained, Esther 9:26, by a brief recapitulation of the events which gave rise to it. Then follows, Esther 9:26 and Esther 9:27, another wordy statement of the fact, that it was by reason of this letter, and on account of what they had seen, i.e., experienced, that the annual celebration of this feast was instituted for a perpetual memorial to all Jews at all times (Esther 9:28 and Esther 9:29).