Abiathar in the Bible Encyclopedia - ISBE

a-bi'-a-thar, ab-i-a'-thar ('ebhyathar, "father of super- excellence," or, "the super-excellent one is father." With changed phraseology these are the explanations commonly given, though "a father remains" would be more in accord with the ordinary use of the stem yathar. The pious Abiathar was still conscious that he had a Father, even after the butchery of his human relatives): 1. The Biblical Account: The Scriptures represent that Abiathar was descended from Phinehas the son of Eli, and through him from Ithamar the son of Aaron; that he was the son of Ahimelech the head priest at Nob who, with his associates, was put to death by King Saul for alleged conspiracy with David; that he had two sons, Ahimelech and Jonathan, the former of whom was, in Abiathar's lifetime, prominent in the priestly service (1 Sam 21:1-9; 22:7 ff; 2 Sam 8:17; 15:27 ff; 1 Ch 18:16; 24:3,6,31). See AHIMELECH; AHITUB. Abiathar escaped from the massacre of the priests at Nob, and fled to David, carrying the ephod with him. This was a great accession to David's strength. Public feeling in Israel was outraged by the slaughter of the priests, and turned strongly against Saul. The heir of the priesthood, and in his care the holy ephod, were now with David, and the fact gave to his cause prestige, and a certain character of legitimacy. David also felt bitterly his having been the unwilling cause of the death of Abiathar's relatives, and this made his heart warm toward his friend. Presumably, also, there was a deep religious sympathy between them...

Link: https://bible-history.com/isbe/A/ABIATHAR/