From Lila by Marilynne Robinson:
“What?” he said. The worrying had worn him out. He gave a sermon once about the disciples sleeping at Gethsemane because they were weary with grief. Sleep is such a mercy, he said. It was a mercy even then.
“I’ve just never had the care of a child.”
“We’ll be fine.” He nestled against her. That sound of settling into the sheets and the covers has to be one of the best things in the world. Sleep is a mercy. You can feel it coming on, like being swept up in something. She could see the light in the room with her eyes closed, and she could smell the snow on the air drifting in. You had to trust sleep when it came or it would just leave you there, waiting.