 Ralph Hood, professor of social psychology and the psychology of religion at the University of Tennessee, who has studied the snake handling movement, indicated in 2003 that the practice is "currently at a fairly low ebb of popularity".A 2013 article by National Public Radio gave a figure of "about 125" churches where snakes are handled, but also indicated that "snake handlers are notoriously private".Practitioners believe serpent handling dates to antiquity and quote the Gospel of Mark and the Gospel of Luke to support the practice