There are at least two people in the Bible named Phinehas. One was the son of Eleazar, and the other was the son of Eli.
Phinehas, the son of Eleazar, was a grandson of Aaron. He was zealous priest. During the desert wandering, Phinehas killed Zimri, an Israelite, and Cozri, a Midianite woman, whom Zimri had brought into the camp (Numbers 25).
This act ended a plague by which God had judged Israel for allowing Midianite women to corrupt Israel with idolatry and harlotry. For such zeal Phinehas and his descendants were promised a permanent priesthood.
Phinehas became the third high priest of Israel, serving for 19 years. In other events in Phinehas' life, he accompanied an army of 12,000 in a war against Midian, in which the Israelites won decisively. He averted a war between the 10 tribes west of the Jordan, with the tribes east of the Jordan, when he learned that the altar built by the east tribes was only a reminder "that the Lord is God", and that it was not an act of idolatry.
He also conveyed the Lord's order to the Israelites to attack the tribe of Benjamin in retaliation for the rape and murder of a woman traveling through the land. In the battle, 25,100 Benjamite warriers died.
For Phinehas' strong defense of the Lord's law, he became a model to zealots of later generations. His descendants were named among those returing from exile in Babylon.
The other Phinehas, the son of Eli, was a brother of Hophni. Phinehas and his brother Hophni were priests but were a disgrace to their priestly office. They were two men without worth, and without regard for the Lord, according to 1 samuel 2:12. They gorged themselves on meat brought to the altar for sacrifice and they treated the offering with contempt.
The brothers also sinned with the women serving the sanctuary. They did not listen to their father, Eli's rebuke, and were eventually killed carrying the Ark of the Covenant in a battle against the Philistines. Eli died when he heard of the death of his two sons, and the Ark had been captured by the Philistines (1 Samuel 4:18)
Phinehas means the "Nubian."
Next person in the Bible: Phinehas, son of Eli