Who was Eli?
Eli was a descendant of Ithamar, the fourth son of Aaron, who exercised the office of high priest in Shiloh at the time of the birth of Samuel. For the first time in Israel, Eli combined in his own person the functions of high priest and judge, judging Israel for 40 years (1 Sam 4:18).
The incidents in Eli's life are few; indeed, the main interest of the narrative is in the other characters who are associated with him. The chief interest centers in Samuel. In Eli's first interview with Hannah (1 Sam 1:12 ff), she is the central figure; in the second interview (1 Sam 1:24 ff), it is the child Samuel. When Eli next appears, it is as the father of Hophni and Phinehas, whose worthless and licentious lives had profaned their priestly office, and earned for them the title "men of Belial" (or "worthlessness").
Eli administered no stern rebuke to his sons, but only a gentle chiding of their greed and immorality. Thereafter he was warned by a nameless prophet of the downfall of his house, and of the death of his two sons in one day (1 Sam 2:27-36), a message later confirmed by Samuel, who had received this word directly from Yahweh Himself (1 Sam 3:11 ff). The prophecy was not long in fulfillment.
During the next invasion by the Philistines, the Israelites were utterly routed, the ark of God was captured, and Hophni and Phinehas were both slain. When the news reached Eli, he was so overcome that he "fell from off his seat backward by the side of the gate; and his neck brake, and he died" (1 Sam 4:18).
The character of Eli, while sincere and devout, seems to have been entirely lacking in firmness. He appears from the history to have been a good man, full of humility and gentleness, but weak and indulgent. His is not a strong personality; he is always overshadowed by some more commanding or interesting figure.
IBSE, "Isaac" (in the public domain) with minor edits.