(Srila Prabhupada in Vrindavan, November, 1977)
"Pure devotee is satisfied only with the service of the Lord. That is pure devotion. Because there is no desire. That is explained here. Ahaituky apratihatā. 'Oh, I am engaged in Kṛṣṇa consciousness because after death I shall go back to home, back to Godhead,' of course, that's a fact. But a pure devotee even does not desire that. He says, 'Wherever Kṛṣṇa will keep me, I shall remain there. It doesn't matter whether heaven or hell. I don't care for it.' Nārāyaṇa-parāḥ sarve na kutaścana bibhyati.
Actually one who is nārāyaṇa-para, pure Kṛṣṇa conscious devotee of the Lord, he's not afraid of going to hell or being promoted to heaven. For him everything is all right.
na kutaścana bibhyati
For heaven or hell, it doesn't matter. That is pure devotion. Anyābhilāṣitā-śūnyam (Brs. 1.1.11), without any desire. That is also desire, that 'I am going back to home, back to Godhead.' But that desire is very highly qualified desire. But a pure devotee does not desire even that. Anyābhilāṣitā-śūnyam (CC Madhya 19.167).They do not desire... What to... They do not desire even to go back to Godhead, and what to desire for being elevated or promoted to the heavenly planet. They simply want, 'Let me remain wherever Kṛṣṇa desires. I may be engaged in His service.' That is pure devotee. That's all.
Anyābhilāṣitā-śūnyaṁ jñāna-karmādy-anāvṛtam (CC Madhya 19.167). Jñānī, they want to merge. Karmī, they want to be elevated to the heavenly planet. Yogī, they wants mystic power. They want something. A pure devotee does not want anything. Therefore it is called ahaitukī. Hetu means cause. 'I am serving God for this cause: I'll go back to home, back to Godhead.' That is also cause. So ahaitukī. No cause. 'Kṛṣṇa is my lovable Deity. I must serve.' That is pure devotion.
Just like Prahlāda Mahārāja was offered all kinds of facilities. 'Prahlāda, you have suffered for Me so much. Now you take whatever you like.' Prahlāda Mahārāja replied, 'My dear Lord, it is not a good proposal. Because I am born of a father, passionate father. Generally, I am passionate, and You are so exalted, You can give me anything.
So I shall be inclined to ask You again. Just like my father had so many opulences. So kindly do not induce me in that way. I am not a merchant, that because I have rendered some service unto You, I expect some return. No. Sa vai vaṇik. It is not business with You. I am your eternal servant.' Oh, just see. This is pure devotee."
(Srila Prabhupada Lecture, London, August 27, 1971)