5 So Ezra rose up and put the leading priests and Levites and all Israel under oath to do what had been suggested. And they took the oath.
6 Then Ezra withdrew from before the house of God and went to the room of Jehohanan son of Eliashib. While he was there, he ate no food and drank no water, because he continued to mourn over the unfaithfulness of the exiles. (Ezra 10:5-6)

Sermon Main Points
1) Ezra fasted
2) Ezra fasted when he mourned over unfaithfulness
3) You should fast
4) You should fast when mourning over unfaithfulness