Regardless of religion, he has to be good enough to begin with to make a team...and the track record of players putting up lots of points on DIII teams and making NBA rosters isn't a good one.
Let's get through that hurdle first, then the discussion can go to whether the team will keep him on the roster long term due to his availability issues caused by his religion.
If you have the talent, I don't think the NBA cares if you are white, black, Hispanic, Asian, Catholic, Jewish, Islamic, Methodist, Baptist, Buddhist, gay, heterosexual, or anything else.
If you can play, a team will find a spot for you. Exhibit #1: Kyrie Irving this year.