I looked through every single one of the 70 results turned up by a search for “alien” in the NIV at bible.crosswalk.com. Couldn’t find what he would have been referring to. The only one that even came close was Lev 25:47:

“If an alien or a temporary resident among you becomes rich and one of your countrymen becomes poor and sells himself to the alien living among you or to a member of the alien’s clan,”

But then it goes on to talk about how the countryman’s relatives can buy him back, nothing about a curse.

Meanwhile, I found a few other interesting tidbits:

Ex 23:9 Do not oppress an alien; you yourselves know how it feels to be aliens, because you were aliens in Egypt.

Le 19:10 Do not go over your vineyard a second time or pick up the grapes that have fallen. Leave them for the poor and the alien. I am the Lord your God.

Le 19:33-34 When an alien lives with you in your land, do not mistreat him. The alien living with you must be treated as one of your native-born. Love him as yourself, for you were aliens in Egypt. I am the Lord your God.

De 24:19 When you are harvesting in your field and you overlook a sheaf, do not go back to get it. Leave it for the alien, the fatherless and the widow, so that the Lord your God may bless you in all the work of your hands.

Eze 22:29 The people of the land practice extortion and commit robbery; they oppress the poor and needy and mistreat the alien, denying them justice.

Ps 146:9 The Lord watches over the alien and sustains the fatherless and the widow, but he frustrates the ways of the wicked.

I don’t know - seems to me like Rev. Young might want to give a few moments’ thought to whom the Lord is watching over and whom he is frustrating.