Exodus 12:43
42 It was a night of vigil for the Lord to bring them out from the land of Egypt, and so on this night all Israel is to keep the vigil to the Lord for generations to come. 43 The Lord said to Moses and Aaron, “This is the ordinance of the Passover. No foreigner may share in eating it. 44 But everyone’s servant who is bought for money, after you have circumcised him, may eat it.
Onkelos Exodus 12:43
42 It is a night to be kept before the Lord for bringing them forth from the land of Mizraim: this is that night before the Lord kept by all the children of Israel in their generations. 43 And the Lord said to Mosheh and to Aharon, This is the rite of the Pascha. Every son of Israel who apostatizes shall not eat of it; 44 but every male servant bought with silver, and thou hast circumcised him, may eat thereof.
Notes and References
"... Onkelos clearly accepts the view that ben naykhar refers to a Jew who apostatized, rather than the other opinion in rabbinic literature that it includes a non-Jew ..."
Drazin, Israel, and Stanley M. Wagner Onkelos on the Torah, Exodus: Understanding the Bible Text (p. 73) Gefen, 2006