“Read me the signs! Tell me my fortune! You're so useful sitting here with all of your books(!)” Her anguish rang in his ears and settled in the pit of his soul. “Giles, I'm sixteen years old. I don't wanna die.”
In that moment... actually several moments later, as the words cooled, as his eye remained transfixed upon the cross where it lay tangled in it's broken chain... He knew. He was as certain as Abraham upon Moriah.
For had he not cried, “God, is there no other way?”
What better answer then, than, “Here. Take this old goat instead.”