Perfection of moral virtue does not wholly take away the passions, but regulates them.

Fear is such a powerful emotion for humans that when we allow it to take us over, it drives compassion right out of our hearts.

The theologian considers sin mainly as an offence against God; the moral philosopher as contrary to reasonableness.

The apostles and their successors are God's vicars in governing the Church which is built on faith and the sacraments of faith. Wherefore, just as they may not institute another Church, so neither may they deliver another faith, nor institute other sacraments.

Because of the diverse conditions of humans, it happens that some acts are virtuous to some people, as appropriate and suitable to them, while the same acts are immoral for others, as inappropriate to them.

It is possible to demonstrate God's existence, although not a priori, yet a posteriori from some work of His more surely known to us.

Man should not consider his material possession his own, but as common to all, so as to share them without hesitation when others are in need.

To one who has faith, no explanation is necessary. To one without faith, no explanation is possible.

As the saints will rejoice in all goods, so will the damned grieve for all goods.