When a man who accepts the Christian doctrine lives unworthily of it, it is much clearer to say he is a bad Christian than to say he is not a Christian.

If God exists, not seeking God must be the gravest error imaginable. If one decides to sincerely seek for God and doesn't find God, the lost effort is negligible in comparison to what is at risk in not seeking God in the first place.

You see, if the height of the mercury [barometer] column is less on the top of a mountain than at the foot of it (as I have many reasons for believing, although everyone who has so far written about it is of the contrary opinion), it follows that the weight of the air must be the sole cause of the phenomenon, and not that abhorrence of a vacuum, since it is obvious that at the foot of the mountain there is more air to have weight than at the summit, and we cannot possibly say that the air at the foot of the mountain has a greater aversion to empty space than at the top.

Once your soul has been enlarged by a truth, it can never return to its original size.

The imagination enlarges little objects so as to fill our souls with a fantastic estimate; and, with rash insolence, it belittles the great to its own measure, as when talking of God.

The world is satisfied with words, few care to dive beneath the surface.

Nature has some perfections to show that she is the image of God, and some defects to show that she is only His image.