'Certain' in the Bible

There was a certain Jew in the citadel of Susa, whose name was Mordecai, the son of Jair, the son of Shimei, the son of Kish, a Benjamite,

Haman said to King Ahasuerus, "There is a certain people scattered abroad and dispersed among the peoples in all the provinces of your kingdom, and their laws are different than other people's. They don't keep the king's laws. Therefore it is not for the king's profit to allow them to remain.