Numbers 15:29

You shall have one law for him that sinneth through ignorance,
&c.] Which enjoins a she goat for a sin offering for such:

[both] for him that is born amongst the children of Israel, and for
the stranger that sojourneth among them;
both sinning through ignorance, the same sacrifice was offered for them, by which atonement was made, and through which their sin was forgiven; by whom are meant homeborn Israelites and proselytes of righteousness, who were under the same laws, and enjoyed the same privileges, as do now believing Jews and Gentiles.