Michael doesn't flinch. 'You can't know,' he says quietly, 'how much you truly love something until it's gone.' 'That's not fair,' I say as I tremble. 'No one said it would be. He tests you, Benji, and he tests Calliel for a supremely simple reason. You are tested because if you aren't, how could you know what you believe in?' 
T.J. Klune, Into This River I Drown
angels, belief, faith, love