You don't need to be religious to enjoy the calming atmosphere of Se Cathedral. Look up when the next mass is scheduled or when you can go for a wander through.
You can keep your money safely tucked away, because it won't cost a cent to visit Se Cathedral. Located in Angra do Heroismo, you'll find some worthwhile attractions not far from this principal church. Why not explore Algar Caves, Angra Harbor and Fortaleza de Sao Joao Batista too?