Ética, Parte V, Proposición 42

Blessedness consists in love towards God (V. xxxvi and note), which love springs from the third kind of knowledge (V. xxxii. Coroll.); therefore this love (III. iii. lix.) must be referred to the mind, in so far as the latter is active; therefore (IV. Def. viii.) it is virtue itself. This was our first point. Again, in proportion as the mind rejoices more in this divine love or blessedness, so does it the more understand (V. xxxii.); that is (V. iii. Coroll.), so much the more power has it over the emotions, and (V. xxxviii.) so much the less is it subject to those emotions which are evil; therefore, in proportion as the mind rejoices in this divine love or blessedness, so has it the power of controlling lusts. And, since human power in controlling the emotions consists solely in the understanding, it follows that no one rejoices in blessedness, because he has controlled his lusts, but, contrariwise, his power of controlling his lusts arises from this blessedness itself. Q.E.D.

I have thus completed all I wished to set forth touching the mind's power over the emotions and the mind's freedom. Whence it appears, how potent is the wise man, and how much he surpasses the ignorant man, who is driven only by his lusts. For the ignorant man is not only distracted in various ways by external causes without ever gaining the true acquiescence of his spirit, but moreover lives, as it were unwitting of himself, and of God, and of things, and as soon as he ceases to suffer, ceases also to be. Whereas the wise man, in so far as he is regarded as such, is scarcely at all disturbed in spirit, but, being conscious of himself, and of God, and of things, by a certain eternal necessity, never ceases to be, but always possesses true acquiescence of his spirit. If the way which I have pointed out as leading to this result seems exceedingly hard, it may nevertheless be discovered. Needs must it be hard, since it is so seldom found. How would it be possible, if salvation were ready to our hand, and could without great labour be found, that it should be by almost all men neglected? But all things excellent are as difficult as they are rare.