Numbers 16:2

2And they rose up before Moses, with a number of the people of Israel, 250 chiefs of the congregation, chosen from the assembly, well-known men.

Numbers 16:17

17And a  let every one of you take his censer and put incense on it, and every one of you bring before the  Lord his censer, b  250 censers; you also, and Aaron, each his censer.”
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