Zadok in Fausset's Bible Dictionary

1. Son of Ahitub, of the house of Eleazar, son of Aaron (1 Chronicles 24:3). Joined David at Hebron after Saul's death, with 22 captains of his father's house. At Absalom's revolt Zadok and the Levites bearing the ark accompanied David in leaving Jerusalem, but at his request returned with the ark and along with Hushai and Abiathar became David's medium of knowing events passing in the city, through Jonathan and Ahimaaz. At Absasalom's death David desired Zadok and Abiathar to persuade the elders of Judah to invite him to return (2 Samuel 15; 2 Samuel 17; 2 Samuel 19). Zadok remained faithful in Adonijah's rebellion when Abiathar joined it. Zadok, with Nathan the prophet, anointed Solomon at Gihon by David's command (a second anointing took place subsequently: 1 Chronicles 29:22). So Solomon put Zadok instead of Abiathar, fulfilling the curse on Eli (1 Samuel 2; 3; 1 Kings 2:27; 1 Kings 2:35; 1 Kings 4:4; 1 Chronicles 29:22). (See ABIATHAR.) David made him ruler over the Aaronites (1 Chronicles 27:17); their number in 1 Chronicles 12:27-28, is said to be 3,700 under Jehoiada. Zadok did not survive to the dedication of Solomon's temple, but Azariah his son or grandson (1 Chronicles 6:8-9) was then high priest (1 Chronicles 6:10; 1 Kings 4:2). His descendants continued in the high priesthood (compare 2 Chronicles 31:10, "Azariah of the house of Zadok chief priest") until the time of Antiochus Eupator. The double high priesthood of Zadok and Abiathar answers to that of the chief priest and second priest (2 Kings 25:18; Luke 3:2 "Annas and Caiaphas being high priest);" compare 2 Chronicles 31:10, "Azariah the chief priest of the house of Zadok." Zadok ministered mainly before the tabernacle at Gibeon (1 Chronicles 16:39). Abiathar bad charge of the ark in Jerusalem; so formerly Eleazar and Ithamar, Hophni and Phinehas, were joint chief priests. Even while the line of Ithamar in the person of Eli was foremost, Eleazar's house held its ground on a kind of parity, Ahitub, Zadok's father, being called "ruler of the house of God" (1 Chronicles 9:11; Nehemiah 11:11)...