It is someone is calling your name over and over and you have to respond or you’ll be trapped in a fog you were never meant to die in.
It’s when you feel life's very core, like how glittering music affects you or the mountains, or great beauty or great pain; when a small child dies or when you hear the stories that meant something.
It is anything that makes you feel eternity for one second.
Just one second.
Listen to it.
Whatever it is, this soul of yours, this calling or cry or pain or joy, this is who you are. Somehow, here is the key.