The chorus of "Believer" is a direct address to the concept and experience of "Pain!" The band tells this character "Pain," "You made me a, you made me a believer, believer." What is this a belief in? It could be in God, the power to overcome, or in other people. Imagine Dragons doesn't make it clear, and I think that's because this is a belief in hope and the ability to believe in things in general.
The lyrics to the song -- written by Reynolds, Tranter, Wayne Sermon, Ben McKee, Daniel Platzman, and the songwriting duo Mattman & Robin -- read, "Oh let the bullets fly, oh let them rain / My life, my love, my drive, it came from / Pain / You made me a, you made me a believer, believer." 041b061a72