“And Balaam the son of Beor they slew with the sword.” For, speaking no longer by the Spirit of God, but setting up another law of fornication contrary to the law of God, this man shall no longer be reckoned as a prophet, but as a soothsayer. For, as he did not continue in the commandment of God, he received the just reward of his evil devices.
Source: Fragments from the Lost Writings of Irenaeus (New Advent)