Mordecai – the son of Jair, of the tribe of Benjamin. It has been alleged that he was carried into captivity with Jeconiah, and hence that he must have been at least one hundred and twenty-nine years old in the twelfth year of Ahasuerus (Xerxes). But the words of Esther do not necessarily lead to this conclusion. It was probably Kish of whom it is said (ver. 6) that he "had been carried away with the captivity."
He resided at Susa, the metropolis of Persia. He adopted his cousin Hadassah (Esther), an orphan child, whom he tenderly brought up as his own daughter. When she was brought into the king’s harem and made queen in the room of the deposed queen Vashti, he was promoted to some office in the court of Ahasuerus, and was one of those who "sat in the king’s gate" (Est 2:21). While holding this office, he discovered a plot of the eunuchs to put the king to death, which, by his vigilance, was defeated. His services to the king in this matter were duly recorded in the royal chronicles.
Haman (q.v.) the Agagite had been raised to the highest position at court. Mordecai refused to bow down before him; and Haman, being stung to the quick by the conduct of Mordecai, resolved to accomplish his death in a wholesale destruction of the Jewish exiles throughout the Persian empire (Est 3:8-15). Tidings of this cruel scheme soon reached the ears of Mordecai, who communicated with Queen Esther regarding it, and by her wise and bold intervention the scheme was frustrated. The Jews were delivered from destruction, Mordecai was raised to a high rank, and Haman was executed on the gallows he had by anticipation erected for Mordecai (6:2-7:10). In memory of the signal deliverance thus wrought for them, the Jews to this day celebrate the feast (9:26-32) of Purim.