Breathing is...a lot harder than Sam expected. Possibly because breathing hadn't been a worry the last time he'd had this much Grace pumped into him. He finds himself gritting his teeth, holding his breath and having to fight to remember to actually breathe.

The reminder was probably a good idea in retrospect.

Even through the pain (and Sam will probably always be more sensitive to Grace than most), he can feel that it's different than what he's been through before. Gentler, more careful. Because Gabriel knows that this is going to cause pain and he's doing his best to keep that to a minimum. Sam bends his head, pressing his forehead to Gabriel's shoulder and just listening to that voice tell him that it'll be all right. That they're almost done.