In Greek mythology, Phineas (also spelled Phineus) was a King of Thrace, son of Agenor who had the gift of prophecy. Zeus, angry that Phineas revealed too much of the plans of the gods, punished him by setting him on an island with a buffet of food. He could eat none of it, however, because the harpies, vicious, winged women, stole the food out of his hands right before he could eat. This continued until the arrival of Jason and the Argonauts. They sent the winged heroes, the Boreads after the harpies. They succeeded in driving the monsters away but did not kill them, as a request from the goddess of the rainbow, Iris, who promised that Phineas would not be bothered by the harpies again. As thanks, Phineas told the Argonauts how to pass the Symplegades.

Apollodorus. Bibliotheke III, xiv, 8; Ovid. Metamorphoses VI, 424-674.

In the Hebrew Bible, Phineas (or Pinchas) was the grandson of Aaron. He killed an Israelite man, Zimri, and a Midianite woman, Cozbi, who were sleeping together (Book of Numbers 25:6-15). This has been used to justify attacking interracial couples, notably by some Christian Identity believers under the banner of the Phineas Priesthood .