“This shall be a statute forever for you: In the seventh month, on the tenth day of the month, you shall afflict your souls, and do no work at all, whether a native of your own country or a ger who dwells among you. For on that day the priest shall make atonement for you, to cleanse you, that you may be clean from all your sins before the Lord. It is a sabbath of solemn rest for you, and you shall afflict your souls. It is a statute forever."
What Does It Say?
Leviticus 16 deals with regulations for the Day of Atonement, perhaps the most sacred day in the Israeli religious calendar. This was the one day that the High Priest would enter into the Holy of Holies, the innermost chamber of the temple, in order to make sacrifice on behalf of the nation.
This day, the 10th day of the seventh month on the lunar calendar, was also a sabbath day regardless of what day of the week it fell. Unlike the other sabbath days, on the Day of Atonement the Israelis are commanded to "afflict [their] souls" in sorrow for the sins the High Priest is purifying them from.
It is also in this passage where we first see religious obligations being explicitly put on foreign nationals dwelling in the land. While Passover was extended to any ger who was willing to have their whole household circumcised and the Sabbaths were extended to all who were part of an Israeli household, observance of the Day of Atonement is required for every person in the land.
Unlike the Passover, it is not limited to the circumcised. It is required of any person who is in Israel. The verb translated as "dwells among" is guwr and includes the sense of temporary living conditions (Elijah guwr with the widow in 1 Kings 17, for example). So a ger who is guwr-ing in the area is a temporary resident.
So regardless what else the Bible says about foreign nationals, requiring respect for local religious festivals from non-believers is on the table.
Next: Leviticus 17