Final answer:
At Vatican Council I, the Pope and bishops emphasized the compatibility of faith with reason and proclaimed the doctrine of papal infallibility.
Step-by-step explanation:
At the Vatican Council I, held in 1869-1870, the Pope and bishops reasserted the relationship between faith and reason by upholding the compatibility of faith with human reason. They emphasized that faith is a supernatural virtue that enables assent to the truths revealed by God. In the context of the Enlightenment, which prioritized human reason and was often critical of religious traditions, the council's declarations aimed to reconcile the use of reason in understanding and interpreting faith. Furthermore, Vatican Council I promulgated the doctrine of papal infallibility, asserting that the Pope, when speaking ex cathedra on matters of faith and morals, is preserved from the possibility of error.