'Separated' in the Bible

The Passover was eaten by the sons (descendants) of Israel (Jacob) who returned from exile and by all those who had separated themselves from the [ceremonial] uncleanness of the nations of the land to join them, in order to seek the Lord God of Israel.

When these things were completed, the officials came to me and said, “The people of Israel and the priests and Levites have not separated themselves from the peoples of the lands, but have committed the repulsive acts of the Canaanites, Hittites, Perizzites, Jebusites, Ammonites, Moabites, Egyptians, and Amorites.