Canon of Justef

The Canon of Justef, from what little I know, focuses on the belief that children born Touched by the Vnquished Gods, meaning they have magical powers not trained in the Church. The basic tenent seems to be that any magic without religious training is heretical or worse, coming from some evil source outside the Pantheon of Sol.

As of Whispers of Ghosts, the Canon of Justef is under review as a potential mistake. There's much more implied, but I'll avoid any more spoilers.