Esther 9:19; Esther 9:27

19 That is why rural Jews—those living in villages—observe the fourteenth of the month of Adar as a day of joy and feasting, a day for giving presents to each other.

27 the Jews took it on themselves to establish the custom that they and their descendants and all who join them should without fail observe these two days every year, in the way prescribed and at the time appointed.