A person who is always absorbed in Kṛṣṇa consciousness is called a devotee of Kṛṣṇa. Śrīla Rūpa Gosvāmī says that all the transcendental qualities discussed previously are also found in the devotees of Kṛṣṇa. The devotees of Kṛṣṇa can be classified into two groups: those who are cultivating devotional service in order to enter into the transcendental kingdom and those who are already in the perfectional stage of devotional service.
A person who has attained the stage of attraction for Kṛṣṇa and who is not freed from the material impasse, but who has qualified himself to enter into the kingdom of God, is called sādhaka. Sādhaka means one who is cultivating devotion in Kṛṣṇa consciousness. The description of such a devotee is found in the Eleventh Canto, Second Chapter, verse 46, of Śrīmad-Bhāgavatam. It is said there that a person who has unflinching faith in and love for the Personality of Godhead, who is in friendship with devotees of Kṛṣṇa, and who is very merciful to the ignorant, raising them to the standard of devotional service, and who is uninterested in nondevotees, is considered to be situated in the position of cultivating devotional service.
When one is found shedding tears by hearing of the pastimes of the Lord, it is to be understood that the blazing fire of material existence will be extinguished by such watering. When there is shivering of the body and the hairs of the body stand up, it is to be understood that the devotee is nearing perfection. An example of a sādhaka cultivating devotional service is Bilvamaṅgala Ṭhākura.
When a devotee is never tired of executing devotional service and is always engaged in Kṛṣṇa conscious activities, constantly relishing the transcendental mellows in relationship with Kṛṣṇa, he is called perfect. This perfectional stage can be achieved in two ways: one may achieve this stage of perfection by gradual progress in devotional service, or one may become perfect by the causeless mercy of Kṛṣṇa, even though he has not executed all the details of devotional service.
There is the following nice statement in the Third Canto, Fifteenth Chapter, verse 25, of Śrīmad-Bhāgavatam, describing a devotee who achieves perfection by regularly executing devotional service: A person who is freed from the false egotism of material existence, or an advanced mystic, is eligible to enter into the kingdom of God, known as Vaikuṇṭha. Such a mystic becomes so joyful by constant execution of the regulative principles of devotional service that he thereby achieves the special favor of the Supreme Lord. Yamarāja, the mighty superintendent of death, is afraid to go near such a devotee; so we can imagine the potency of advanced devotional service, especially when devotees sit together and engage in talking of the pastimes of the Supreme Personality of Godhead. Those devotees express their feelings in such a way that they automatically melt with ecstasy, and many transcendental symptoms become manifested in their bodies. Anyone desiring advancement in devotional service must follow in the footsteps of such devotees.
Prahlāda Mahārāja said that no one can attain the perfectional stage of devotional service without bowing down before exalted devotees. Learned sages like Mārkaṇḍeya Ṛṣi attained perfection in devotional service simply by executing such regulative principles of service.
A person's achieving perfection in devotional service simply by the causeless mercy of the Lord is explained in Śrīmad-Bhāgavatam in connection with the brāhmaṇas and their wives who were engaged in performing yajña, or sacrifice. When the wives of the brāhmaṇas were favored by Lord Kṛṣṇa and immediately attained the ecstasy of love of Godhead, their husbands said, "How wonderful it is that although these women have undertaken no reformatory performances such as accepting the sacred thread, have not resided in the monasteries of the spiritual master, have not observed the strict principles of celibacy, have not undergone any austerities and have not philosophized upon the observance of ritualistic ceremonies, they still have attained the favor of Kṛṣṇa, which is aspired after even by great mystics! How wonderful it is that these women have attained such perfection, while we, although brāhmaṇas who have performed all the reformatory activities, cannot attain to this advanced stage!"
There is a similar statement by Nārada, addressed to Śukadeva Gosvāmī: "My dear Śukadeva Gosvāmī, you never took the trouble to reside under the care of a spiritual master, and yet you have attained such a great status of transcendental knowledge. You never took the trouble to undergo severe austerities, and still, how wonderful it is that you have been situated in the most perfect stage of love of Godhead."
Śukadeva Gosvāmī and the wives of the brāhmaṇas performing yajña are vivid examples of devotees who achieved the perfectional stage of devotional service by the grace of the Supreme Personality of Godhead.