Kings III 22:21

21 And there came forth a spirit and stood before the Lord, and said, I will deceive him.

Kings III 22:21 In-Context

19 And Michaias said, Not so, not I: hear the word of the Lord; not so. I saw the God of Israel sitting on his throne, and all the host of heaven stood about him on his right hand and on his left.
20 And the Lord said, Who will deceive Achaab king of Israel, that he may go up and fall in Remmath Galaad? and one spoke one way, and another another way.
21 And there came forth a spirit and stood before the Lord, and said, I will deceive him.
22 And the Lord said to him, Whereby? And he said, I will go forth, and will be a false spirit in the mouth of all his prophets. And he said, Thou shalt deceive him, yea, and shalt prevail: go forth, and do so.
23 And now, behold, the Lord has put a false spirit in the mouth of all these thy prophets, and the Lord has spoken evil against thee.

The Brenton translation of the Septuagint is in the public domain.