Sifrei Bamidbar 109

(Bamidbar 15:15) "The congregation (— one statute shall there be for you, etc."): This (Ibid. 2, "the sons of Israel") tells one only of the men (as bringing libations). Whence do I derive (the same for) the women? From "the congregation." "One statute shall there be for you and for the stranger that sojourns (among you"): Because this speaks of Israel, the proselytes must be (specially) included. "an everlasting statute unto your generations": that this (the libations) obtain in all the generations. "As you, thus shall the stranger be before the L-rd": What is the intent of this? From (Shemot 28:38) "And it (the head-plate) shall be on his (Aaron's) forehead always for acceptance for them before the L-rd," I might think that this applied only to (native-born) Israelites. Whence do I derive (the same for) proselytes? From "As you, thus shall the stranger be before the L-rd." (Ibid. 16) "One Torah and one judgment shall there be for you and for the stranger who sojourns among you": Scripture hereby likens the proselyte to the native-born in respect to all the mitzvoth of the Torah.