Ezra 10:5-6

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. 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.