(Kṛṣṇa does not require any service from you but the love. If you can achieve Kṛṣṇa, then you will feel that "I don’t require anything more") 



Dhruva Mahārāja said when he saw Viṣṇu, he says, svāmin kṛtārtho ’smi varaṁ na yāce (CC Madhya 22.42) "My dear Lord, my all desires and demands are now fulfilled. I don’t want anything." This is Kṛṣṇa consciousness. If actually one becomes Kṛṣṇa conscious, he has no more demand for anything material."
(His Divine Grace A.C.Bhaktivedanta Swami Srila Prabhupada Lecture, March 19, 1969, Hawaii)