Balaam (Heb. Bil'am), a soothsayer and diviner of Pethor, on "the river" (Euphrates), whom Balak, king of Moab, alarmed at the discomfiture of his neighbors the Amorites by the Hebrews, sent for to pronounce a curse upon the invaders. Balaam refused, saying that he could not curse the people whom God had blessed; but upon being further urged, he agreed to say only what should be commanded by God. He set out, riding upon an ass; but on the way he was met by the angel of the Lord, visible to the ass, but not to the rider. The ass refused to pass the opposing angel, and three times turned out of the way, being each time beaten by Balaam. At last the ass spoke in a human voice, asking why he had been beaten. Then Balaam's eyes were opened, and he saw the angel of the Lord standing with a drawn sword to bar his way. The angel told him to go on to Balak, but he must only say what should be commanded to him. Balaam went to Balak, and after due sacrifices delivered his message, which proved to be a blessing upon the Hebrews, instead of the desired curse. This was repeated four times, with the same result; and on the last occasion Balaam predicted that the Israelites should overthrow Moab, Edom, Amalek, and other neighboring tribes.

Some Biblical critics consider the story of Balaam (Numbers xxii.-xxiv.) as an interpolation; other expounders have interpreted the speaking of the ass as a vision or trance in which the diviner thought he saw an angel, and fancied that he heard the ass speaking.