Was Abiathar the son of Ahimelech or his father?

There were two priests called Ahimelech: Abiathar’s father, and Abiathar’s son, named after his grandfather. The elder Ahimelech was killed by Saul at Nob, and his son Abiathar escaped to David, bringing the ephod with him (1 Samuel 22:18–20; 23:6). Years later, when David was king, a younger Ahimelech, “the son of Abiathar”, served as a leading priest with Zadok (2 Samuel 8:17). Chronicles shows that this was no slip of the pen. It names him three times in its account of David’s last years: as “Ahimelech of the sons of Ithamar”, Abiathar’s priestly line, beside Zadok of the line of Eleazar (1 Chronicles 24:3), as “Ahimelech the son of Abiathar” (24:6), and again with Zadok (24:31).

Naming a boy after his grandfather was common in Israel; the high-priestly line itself repeats Amariah, Ahitub and Zadok within a few generations (1 Chronicles 6:7–12). Abiathar was still priest at the start of Solomon’s reign (1 Kings 2:26–27; 4:4), and Keil and Delitzsch, following Bertheau and Oehler, suggest that his son Ahimelech, then a grown man, shared or carried out his duties, perhaps when his father was ill or otherwise prevented. So both statements are true: Abiathar was the son of one Ahimelech and the father of another.

The names transposed

Some scholars think that 2 Samuel 8:17 originally read ‘Abiathar the son of Ahimelech’, and that a scribe reversed the names. Keil and Delitzsch rejected this, since Chronicles names Ahimelech son of Abiathar several times, and every passage would have to be altered.