User blog comment:Jopjopjop/Volume 19 Spoilers/@comment-121.54.46.23-20150114225751/@comment-16281343-20150115025154

THe piece of the holy grail is from the original grail not the Sacred Gear. The piece is inside the pendant of Valerie.

And Strada didn't trick DxD. He used the rebellion for the sake of everyone and for the Church to change their views.