I have trouble with the last part of the following sentence :
Ita vero isti desipiunt, ut illis libris, quos eum scripsisse existimant, dicant contineri eas artes, quibus eum putant illa fecisse miracula, quorum fama ubique percrebuit : quod existimando seipsos produnt quid diligant, et quid affectent.
"They even are so mad as to say that those books, which they believe he (=Christ) has written, contain the magical know-how by which he has performed the miracles whose fame has spread everywhere : by believing this they betray themselves..."
Could there be some kind of punctuation after produnt ? Are the two quid to be understood as object of produnt, like seipsos ?
> "the betray themselves, what they like and what they seek."
I guess part of my trouble is also that I did not expect quid but quod here.