LXX Num 9:14

ἐὰν δὲ προσέλθῃ πρὸς ὑμᾶς προσήλυτος ἐν τῇ γῇ ὑμῶν καὶ τὸ πάσχα κυρίῳ, κατὰ τὸν νόμον τοῦ πάσχα καὶ κατὰ τῆ αὐτοῦ ποιήσει αὐτό· νόμος εἷς ἔσται ὑμῖν καὶ τῷ προσηλύτῳ καὶ τῆς γῆς.

If a foreigner dwelling among you wants to observe the Passover to the LORD, he is to do so according to the Passover statute and its ordinances. You are to apply the same statute to both the foreigner and the native of the land.’”