Exodus 12:43 in the King James Version
And the LORD said unto Moses and Aaron, This is the ordinance of the passover: There shall no stranger eat thereof:
Context
42 It is a night to be much observed to the LORD for bringing them out from the land of Egypt. This is that night of the LORD, to be much observed by all the children of Israel throughout their generations.
43 The LORD said to Moses and Aaron, “This is the ordinance of the Passover. No foreigner shall eat of it,
44 but every man’s servant who is bought for money, when you have circumcised him, then shall he eat of it.