I don't think they can. Idk if I remember things right, but only those with magic could join the clergy, right? And only noble-born got magic too.
Only members have the clergy of a certain rank have the authority/ability/knowledge of how to bestow priesthood to another person. It can be done TO anyone, but not BY anyone.
None of the priest characters in our cast have the ability to make new priests, from our current knowledge (they'd need to be at least a bishop, I assume).
Thanks
Love you Zeze. On another topic, I won't reread right now but can't they turn the people without magic into priest? That way they would get more spare lives