Ezra 6:21

And the children of Israel, which were come again out of
captivity
The tribes of Judah and Benjamin, with some of the ten tribes mixed with them:

and all such as had separated themselves unto them, from the filthiness
of the Heathen of the land, to seek the Lord God of Israel, did eat;
such of the Gentiles in the dominions of Babylon, and came with the Jews from thence, who were enlightened into the knowledge and worship of the true God, and not only renounced their idolatry, here called filthiness, but were circumcised, and embraced the religion of the Jews, and so were proselytes of righteousness, as they call them; or otherwise they would not have been allowed to eat of the passover, as they did, ( Exodus 12:48 ) .