"And religious music and the sort of symbolism of it and everything. But I had this idea. Actually, I sort of dreamt it. I woke up - just before waking up one morning, I sort of dreamt this song or the idea of it and the first little bit of it. And I jumped out of bed and I thought, well, you're still asleep. You're going to forget this in a minute - you know, like you do when you've had a dream."