The issue of loss of faith is a real issue but this has nothing whatsoever to do with race since people of all races are Christian believers.
If a person of the same race or a different race is not a Christian then the New Testament certainly forbids the marriage. The Old Testament principle is essentially the same. The people of the Canaanites were pagan idolaters of the most vile kind. If they were around today, many of them would be locked up for their bestiality and child-sacrifices. Both Ruth the Moabite and Rahab the inhabitant of Jericho were taken in by the Israelites and Ruth is in the family line of Jesus Christ through her marriage to Boaz.
Thus it is, as always good to understand what the Bible is actually saying and to read it in context.