Jehoiada (Hebrew: יְהוֹיָדָע Yəhōyāḏā‘, "Yahweh knows") in the Hebrew Bible, was a prominent priest during the reigns of Ahaziah, Athaliah, and Joash. Jehoiada became the brother-in-law of King Ahaziah as a result of his marriage with princess Jehosheba. Both Jehosheba and Ahaziah were children of King Jehoram of Judah. Ahaziah died a year after assuming the throne, which was then usurped by his mother Athaliah, who ordered the execution of all members of the royal family.
Jehosheba and Jehoiada rescued Athaliah's one-year-old grandson, Joash, from Athaliah's slaughter. For six years, they hid the sole surviving heir to the throne within the Temple. Jehoiada was instrumental in the staging of the coup that dethroned and killed Athaliah. Under Jehoiada's guidance, Baal-worship was renounced and the altar and temple of Baal were destroyed.
Jehoiada is also noteworthy for the national covenant that he made "between him, and between all the people, and between the king, that they should be the LORD's people" (2 Chronicles 23:16). Jehoiada lived 130 years and was buried very honorably among the kings in the city of David. Jehoiada's son, Zechariah, was later martyred by King Joash.