Easton's Bible Dictionary (1897)
Father of abundance, or my father excels, the son of Ahimelech the high priest. He was the tenth high priest, and the fourth in descent from Eli. When his father was slain with the priests of Nob, he escaped, and bearing with him the ephod, he joined David, who was then in the cave of Adullam (1 Sam. 22:20-23; 23:6). He remained with David, and became priest of the party of which he was the leader (1 Sam. 30:7). When David ascended the throne of Judah, Abiathar was appointed high priest (1 Chr. 15:11; 1 Kings 2:26) and the “king’s companion” (1 Chr. 27:34).
Meanwhile Zadok, of the house of Eleazar, had been made high priest. These appointments continued in force till the end of David’s reign (1 Kings 4:4). Abiathar was deposed (the sole historical instance of the deposition of a high priest) and banished to his home at Anathoth by Solomon, because he took part in the attempt to raise Adonijah to the throne. The priesthood thus passed from the house of Ithamar (1 Sam. 2:30-36; 1 Kings 1:19; 2:26, 27). Zadok now became sole high priest.
” But from 1 Sam. 22, we learn explicitly that this event took place when Ahimelech, the father of Abiathar, was high priest. The apparent discrepancy is satisfactorily explained by interpreting the words in Mark as referring to the life-time of Abiathar, and not to the term of his holding the office of high priest. It is not implied in Mark that he was actual high priest at the time referred to. Others, however, think that the loaves belonged to Abiathar, who was at that time (Lev. 24:9) a priest, and that he either himself gave them to David, or persuaded his father to give them.
Smith's Bible Dictionary (1863)
e. liberal), High priest and fourth in descent from Eli. ) Abiathar was the only one of the all the sons of Ahimelech the high priest who escaped the slaughter inflicted upon his father’s house by Saul, in revenge for his father’s house by Saul, in revenge of his having inquired of the Lord for David and given him the shew-bread to eat. (1 Samuel 22:1) ... Abiathar having become high priest fled to David, and was thus enabled to inquire of the Lord for him.
(1 Samuel 23:9; 30:7; 2 Samuel 2:1; 5:19) etc. He adhered to David in his wanderings while pursued by Saul; he was with him while he reigned in Hebron, and afterwards in Jerusalem. (2 Samuel 2:1-3) He continued faithful to him in Absalom’s rebellion. (2 Samuel 15:24,29,35,36; 17:15-17; 19:11) When, however, Adonijah set himself up fro David’s successor on the throne, in opposition to Solomon, Abiathar sided with him, while Zadok was on Solomon’s side. For this Abiathar was deprived of the high priesthood.
Zadok had joined David at Hebron, (1 Chronicles 12:28) so that there was henceforth who high priests in the reign of David, and till the deposition of Abiathar by Solomon, when Zadok became the sole high priest.
Hastings' Dictionary of the Bible (1898) & Schaff's Bible Dictionary
ABI'ATHAR (father of abundance, i. e. liberal), the tenth high priest of the Jews, and fourth in descent from Eli. 1 Sam 22:20. 1 Sam 22. Abiathar fled to David at Keilah, and told him what Saul had done. David received him, and he afterward became high priest.
Thus there were two high priests in Israel at the same time — Abiathar, in the party of David, and Zadok, in the party of Saul, 2 Sam 8:17; but, in consequence of his supporting Adonijah in his pretensions to the throne of David, Solomon, upon becoming king, thrust Abiathar out of the priesthood, 1 Kgs 2:27, and conferred the office exclusively upon Zadok. See Zadok.
Thus was fulfilled the word of God to Eli, 1 Sam 2:31; for Abiathar was the last of the priests of the house of Ithamar, to which Eli belonged; and Zadok, who succeeded him, was of the family of Eleazar; and so the priesthood passed into its former channel. Abiathar, mentioned in Mark 2:26, has been supposed by some to be the same with Ahimelech. The most probable solution of the difficulty is, perhaps, that Abiathar and Ahimelech may have been hereditary names in the family, and therefore were both borne by the same person.
Hence the name Abiathar, being that of David's friend, would be more commonly used than Ahimelech. This theory also accounts for the substitution of one name for another in 2 Sam 8:17; 1 Chr 18:16, and 1 Chr 24:3, 1 Chr 24:6, 1 Chr 24:31. The facts to which the Gospel alludes in the passage cited are fully stated in 1 Sam 21.
Hitchcock's Bible Names (1869)
excellent father; father of the remnant