Sefer HaBahir 11

1[Rabbi Bun continued,] And what is ['Elohim also created one opposite the other' (Ecclesiastes 7:14)? [God] created bohu and put its place in peace and created tohu and put its place in evil. Bohu is in peace as it is said 'The One Who creates peace in His heights' (Job 25:2). This teaches that Michael, the right-hand prince of the Blessed Holy One, is water and hail, and Gavriel, the left-hand prince of the Blessed Holy One, is fire. And the Prince of Peace decides between them. Thus it was written, 'The One Who creates peace in His heights.' (Job 25:2)"