Mordecai (/ˈmɔːrdɪkaɪ, mɔːrdɪˈkeɪaɪ/; also Mordechai; Hebrew: מָרְדֳּכַי, Modern: Mŏrdoḵay, Tiberian: Mārdoḵay,[a] IPA: [moʁdeˈχaj]) is one of the main personalities in the Book of Esther in the Hebrew Bible. He is described in Tanna Devei Eliyahu as being the son of Jair, of the tribe of Benjamin and member of the Sanhedrin. Mordecai was also the cousin and guardian of Esther, who became queen of Persia under the reign of Ahasuerus (Xerxes I). Mordecai's loyalty and bravery are highlighted in the story as he helps Esther foil the plot of Haman, the king's Vizier, to exterminate the Jewish people.
–Wikipedia