Prasanna-manaso. Unless you become joyful in your mind by executing devotional service . . . evaṁ prasanna. Prasanna means joyful. Manasa, manasa means mind. When you are fully joyful in your mind by executing devotional service . . . evaṁ prasanna-manaso bhagavad-bhakti-yogataḥ. How one can become joyful? Simply by executing Kṛṣṇa consciousness. Not otherwise. It is not possible.
So austerity means we are not imposing upon you that you go to the forest and you live in a cave or you don't eat or don't see any human being; you just meditate for three hundred years. No. That is not possible. That is not possible. You cannot go to the forest, you cannot go to the mountain, neither you can meditate. All these are not recommended in this age. That is not possible. If somebody imitates or tries to imitate, he is simply wasting time. Only austerity is that don't have illicit sex life just like cats and dogs.
Because marriage is recommended in the human society. There is no marriage in cat society, dog society, hog society. Any human society you take, either in the Western world or in the Eastern world, or in Christian society, Hindu society, Muhammadan society—in every civilized human society there is a ceremony called marriage. And that is also Vedic system, that one should not have any illicit sex life, but one should be combined according to religious rite and live peacefully and execute Kṛṣṇa consciousness. This much austerity.