Ezra 6:20-21
20 The priests and Levites had purified themselves and were all ceremonially clean. The Levites slaughtered the Passover lamb for all the exiles, for their brothers the priests and for themselves.
21 So the Israelites who had returned from the exile ate it, together with all who had separated themselves from the unclean practices of their Gentile neighbors in order to seek the Lord, the God of Israel.