Esther 9:31

to establish these days of the Purim, in their set times, according as Mordecai the Jew and Esther the queen had enjoined upon them, and according as they had enjoined upon their own soul, and upon their seed, - the story of the fastings and of their outcry.

Esther 4:3

And, throughout every province, whithersoever the word of the king and his edict came, was great mourning to the Jews, and fasting and weeping, and lamentation, - sackcloth and ashes, were spread out for many.

Esther 4:16

Go! gather ye together all the Jews who are to be found in Shusan, and fast ye for me - and neither eat nor drink - three days, night nor day, and, I and my maidens, will fast so, - and, in this manner, will I go in unto the king, though it is not according to the law, and, when I have perished, I have perished!

Jonah 3:2-9

Arise, get thee unto Nineveh, the great city, - and cry against it the cry that I am bidding thee.

Treasury of Scripture Knowledge

Summary

To confirm these days of Purim in their times appointed, according as Mordecai the Jew and Esther the queen had enjoined them, and as they had decreed for themselves and for their seed, the matters of the fastings and their cry.

And for their seed

The fastings

Bible References

And for their seed

Esther 9:27
The Jews established and took upon themselves - and upon their seed, and upon all who should join themselves unto them, that it might not pass away, that they would continue to keep these two days, according to the writing concerning them and at their set time, - always year by year.

The fastings

Esther 4:3
And, throughout every province, whithersoever the word of the king and his edict came, was great mourning to the Jews, and fasting and weeping, and lamentation, - sackcloth and ashes, were spread out for many.
Jonah 3:2
Arise, get thee unto Nineveh, the great city, - and cry against it the cry that I am bidding thee.