Rūpa Gosvāmī defines the first part of devotional practice, or vaidhi-bhakti, as follows: "When there is no attachment or no spontaneous loving service to the Lord, and one is engaged in the service of the Lord simply out of obedience to the order of the spiritual master or in pursuance of the scriptures, such obligatory service is called vaidhi-bhakti."
These principles of vaidhi-bhakti are also described in Śrīmad-Bhāgavatam, Second Canto, First Chapter, verse 5, where Śukadeva Gosvāmī instructs the dying Mahārāja Parīkṣit as to his course of action. Mahārāja Parīkṣit met Śukadeva Gosvāmī just a week before his death, and the King was perplexed as to what should be done before he was to pass on. Many other sages also arrived there, but no one could give him the proper direction. Śukadeva Gosvāmī, however, gave this direction to him as follows: "My dear King, if you want to be fearless in meeting your death next week (for actually everyone is afraid at the point of death), then you must immediately begin the process of hearing and chanting and remembering God." If one can chant and hear Hare Kṛṣṇa and always remember Lord Kṛṣṇa, then he is sure to become fearless of death, which may come at any moment.
In the statements of Śukadeva Gosvāmī it is said that the Supreme Personality of Godhead is Kṛṣṇa. Therefore Śukadeva recommends that one should always hear about Kṛṣṇa. He does not recommend that one hear and chant about the demigods. The Māyāvādīs (impersonalists) say that one may chant any name, either that of Kṛṣṇa or those of the demigods, and the result will be the same. But actually this is not a fact. According to the authorized version of Śrīmad-Bhāgavatam, one has to hear and chant about Lord Viṣṇu (Kṛṣṇa) only.