Under the Catholic Church the Bible was number one on the list of banned books ('The Index') and it was only written in Latin (vernacular translations were a capital offence) and the only people allowed to interpret it were the clergy. One of the core elements of the Reformation was the translation into vernacular of the Bible and the propagation of the idea that anyone could interpret it. The explosion of interpretations and beliefs during that period is often cited as one of the driving forces behind the viciousness of the wars of religions. (Apologies for not having citations on hand, this was mostly pulled from memory)