Exodus 22:20: “You shall not oppress or afflict a resident alien, for you were once aliens residing in the land of Egypt.

Hebrews 13:1: “Do not neglect hospitality, for through it some have unknowingly entertained angels.”

Matthew 25:35: “For I was hungry and you gave me food, I was thirsty and you gave me drink, a stranger and you welcomed         me.”

Leviticus 19:34: “You shall treat the alien who resides with you no differently than the natives born among you; you shall love the alien as yourself; for you too were once aliens in the land of Egypt.y I, the LORD, am your God.”

http://www.usccb.org/bible/