Guest: I have a question.
Guest: What's the purpose of deep sleep as one of the bases of our life?
Prabhupāda: Deep sleep is forgetfulness. That's all.
Guest: Forgetfulness when I sleep, but...
Prabhupāda: Yes, when you become tired, you, or by intoxication, you sleep deep. This is... this is material existence. Either this material activity or material dreaming or material deep sleep, they're all material. In spiritual life, oh, there is no sleep. There is no deep sleep or slight sleep or dream. That is everything actual. (pause) Any other question?
Guest: When you're actually Kṛṣṇa conscious, what... my question before, I meant, when you're actually Kṛṣṇa conscious, do you just exist and know all and enjoy all, or do you have any activities at that time?
Prabhupāda: Well, unless you have got enjoyment, how can you continue your activities? Do you think that in any activity which you... in which you do not feel happy or enjoy, do you, can you continue that activity? No. Therefore Kṛṣṇa consciousness means the more you become active in Kṛṣṇa conscious, the more you become joyful. Ānandamayo 'bhyāsāt (Vedānta-sūtra 1.1.12). That means your real life becomes revealed, joyful life. And as you become joyful, so you are more energetic to work for Kṛṣṇa. That will give you impetus.
It is not a dead, stereotyped thing. It is dynamic force. The more you work for Kṛṣṇa, the more you feel energetic, the more you feel light. It is practical. Ask so many students. They are feeling, yes, joyful. There are so many attraction on material life. Oh, how they can forget? How they can forget?
Especially in your country, there are so many facilities of material enjoyment, and how they can forget all these unless they have got some enjoyment? So it is practical. The more you engage yourself in Kṛṣṇa consciousness, the more you feel joy, joyer. That is joyful life.
And the Caitanya-cari... Caitanya Mahāprabhu said, ānandāmbudhi-vardhanam (CC Antya 20.12). Ānandāmbudhi-vardhanam means there is a ocean of joy. Now this ocean is stagnant; it does not increase. But that ānandāmbudhi, the ocean of joy, transcendental bliss, that increases. Increases. And there is unlimited space also to allow that increment. Ānandāmbudhi-vardhanaṁ prati-padaṁ pūrṇāmṛtāsvādanam: "In every step you'll feel, oh, that spiritual bliss."
Paraṁ vijāyate śrī-kṛṣṇa-saṅkīrtanam: "All glories to Śrī Kṛṣṇa saṅkīrtana." Just like in the morning lecture we were, er, Caitanya Mahāprabhu is explaining His practical experience, how He's feeling joyful. So this is practical. There is nothing theoretical. This is standard, practical and easy. This is the beauty of this movement.
(Srila Prabhupada Lecture, San Francisco, March 13, 1967)