1 Kings 17:1, 7

Now Elijah the Tishbite, who was of the settlers of Gilead, said to Ahab, “As the LORD, the God of Israel lives, before whom I stand, there shall be neither dew nor rain these years, except by my word.” [Deut 11:16, 17]

It happened after a while that the brook dried up, because there was no rain in the land.