Absorption of intelligence in the personal service of Kṛṣṇa and full consciousness of Kṛṣṇa always are the path of self-realization and liberation. Without being unnecessarily agitated, if we take to the process of Kṛṣṇa consciousness by constantly chanting Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare, the cycle of birth and death can be stopped for good.
(Srimad Bhagavatam----3:31:21----purport).

Anyone desiring to become expert in the service of Śrī Śrī Rādhā and Kṛṣṇa should always aspire to be under the guidance of Svarūpa Dāmodara Gosvāmī, Rūpa Gosvāmī, Sanātana Gosvāmī and Raghunātha dāsa Gosvāmī.
(Sri Caitanya Caritamrta----1:5:202----purport).

We are saying, "Chant the Hare Kṛṣṇa mahā-mantra, be freed from all the complexities of life, and realize Kṛṣṇa, the Supreme Personality of Godhead. Engage in His devotional service and perfect your life so that you can return home, back to Godhead."
(Sri Caitanya Caritamrta----2:25:198----purport).

If one is transcendentally absorbed in Kṛṣṇa's service, then his next body will be transcendental (spiritual), not material. Therefore the chanting of Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare is the best process for successfully changing one's state of being at the end of one's life.
(Bhagavad-Gita----8:6----purport).

Hanumānjī applied his anger in this way. He was a great devotee of Lord Rāmacandra, and he utilized his anger to set fire to the kingdom of Rāvaṇa, a nondevotee demon. Thus kāma (lust) can be utilized to satisfy Kṛṣṇa, and krodha (anger) can be utilized to punish the demons. When both are used for Kṛṣṇa's service, they lose their material significance and become spiritually important.
(Srimad Bhagavatam----4:25:24----purport).

Prahlāda Mahārāja said: Hearing and chanting about the transcendental holy name, form, qualities, paraphernalia and pastimes of Lord Viṣṇu, remembering them, serving the lotus feet of the Lord, offering the Lord respectful worship with sixteen types of paraphernalia, offering prayers to the Lord, becoming His servant, considering the Lord one's best friend, and surrendering everything unto Him (in other words, serving Him with the body, mind and words)—these nine processes are accepted as pure devotional service. One who has dedicated his life to the service of Kṛṣṇa through these nine methods should be understood to be the most learned person, for he has acquired complete knowledge.
(Srimad Bhagavatam----7:5:23-24----translation and purport).

One who is actually intelligent gives up all material desires and engages in the transcendental service of Kṛṣṇa.
(Teachings of Lord Caitanya).

If one does not completely devote his mind and body to the service of the Lord, he does not actually become a sannyāsī. It is not simply a matter of changing dress. One who works devotedly for the satisfaction of Kṛṣṇa is a sannyāsī. The dress is not sannyāsa, but the attitude of service to Kṛṣṇa is.
(Sri Caitanya Caritamrta----2:3:6----purport).

Persons who have acted piously in previous lives and in this life and whose sinful actions are completely eradicated are freed from the dualities of delusion, and they engage themselves in My service with determination.
(Bhagavad-Gita----7:28----translation)

The thoughts of My pure devotees dwell in Me, their lives are fully devoted to My service, and they derive great satisfaction and bliss from always enlightening one another and conversing about Me.
(Bhagavad-Gita----10:9----translation).

One may be a śūdra, vaiśya or woman, but if one is situated in the service of the Lord in Kṛṣṇa consciousness, one should not be considered strī, śūdra, vaiśya or lower than śūdra. Though a person may be from a lowborn family, if he is engaged in the Lord's service he should never be considered to belong to a lowborn family.
(Sri Caitanya Caritamrta----2:8:36----purport).

Without serving Kṛṣṇa according to the vidhi-mārga regulative principles of the pāñcarātrika-vidhi, unscrupulous persons want to jump immediately to the rāga-mārga principles. Such persons are called sahajiyā. There are also demons who enjoy depicting Kṛṣṇa and His pastimes with the gopīs, taking advantage of Kṛṣṇa by their licentious character. These demons who print books and write lyrics on the rāga-mārga principles are surely on the way to hell.
(Srimad Bhagavatam----4:24:45-46----purport).

One should desire to become like a dog in strictly following a devotee. Kṛṣṇa is in the hand of a devotee. Adurlabham ātma-bhaktau. Thus without the favor of a devotee, one cannot directly approach Kṛṣṇa, what to speak of engaging in His service.
(Srimad Bhagavatam----10:10:25----purport).