The materialistic men want to work hard and enjoy fruitive results for sense enjoyment. Thus they are committing many types of sins at every step of life. Those, however, who are consciously engaged in the devotional service of the Lord are transcendental to all varieties of sin and virtue. Their activities are free from the contamination of the three modes of material nature. For the devotees there is no need for performance of prescribed sacrifices because the very life of the devotee is a symbol of sacrifice. But persons who are engaged in fruitive activities for sense enjoyment must perform the prescribed sacrifices because that is the only means to get free from the reaction of all sins committed by fruitive workers. Sacrifice is the means for counteracting such accumulated sins. The demigods are pleased when such sacrifices are performed, just as prison officers are satisfied when the prisoners are turned into obedient subjects. Lord Caitanya, however, has recommended only one yajña, or sacrifice, called the saṅkīrtana-yajña, the chanting of Hare Kṛṣṇa, in which everyone can take part. Thus both devotees and fruitive workers can derive equal benefit from the performances of saṅkīrtana-yajña.
(Srimad Bhagavatam----1:16:20----purport).

Even in the nonliberated stage, a living entity can be directly engaged in the transcendental loving service of the Personality of Godhead Lord Kṛṣṇa or His plenary expansions like Rāma and Narasiṁha. Thus, with the proportionate improvement of such transcendental devotional service, the devotee makes definite progress toward brahma-gatim or ātma-gatim, and ultimately attains kapilasya gatim, or the abode of the Lord, without difficulty. The antiseptic potency of devotional service to the Lord is so great that it can neutralize the material infection even in the presentlife of a devotee. A devotee does not need to wait for his next birth for complete liberation.
(Srimad Bhagavatam----2:7:3----purport).

The time factor cannot affect the span of life of the devotees. In Bhagavad-gītā it is stated that a little execution of devotional service saves one from the greatest danger. The greatest danger is transmigration of the soul from one body to another, and only devotional service to the Lord can stop this process. It is stated in the Vedic literatures, hariṁ vinā na mṛtim taranti: without the mercy of the Lord, one cannot stop the cycle of birth and death. In Bhagavad-gītā it is stated that only by understanding the transcendental nature of the Lord and His activities, His appearance and disappearance, can one stop the cycle of death and go back to Him.
(Srimad Bhagavatam----3:21:18----purport).

The symptoms of pure devotees are described in this verse. The pure devotee is never interested in material topics. Śrī Caitanya Mahāprabhu has strictly prohibited His devotees to talk about worldly matters. Grāmya-vārtā nā kahibe: [Cc. Antya 6.236] one should not indulge in talking unnecessarily about news of the material world. One should not waste time in this way. This is a very important feature in the life of a devotee. A devotee has no other ambition than to serve Kṛṣṇa, the Supreme Personality of Godhead. This Kṛṣṇa consciousness movement was started to engage people twenty-four hours daily in the service of the Lord and in His glorification. The students in this institution engage in the cultivation of Kṛṣṇa consciousness from five in the morning to ten at night. They actually have no opportunity to waste their time unnecessarily by discussing politics, sociology and current events. These will go their own way. A devotee is concerned only with serving Kṛṣṇa positively and seriously.
(Srimad Bhagavatam----5:12:13----purport).

A devotee's life and duty are very well explained herein. As soon as a devotee can chant the holy name and glories of the Supreme Lord, he certainly comes to the liberated position. Attachment for glorifying the Lord by hearing and chanting the holy name and activities of the Lord (śravaṇaṁ kīrtanaṁ viṣṇoḥ [SB 7.5.23]) certainly brings one to the position where material contamination is absent. One should chant the bona fide songs received from the disciplic succession. In Bhagavad-gītā it is said that the chanting is powerful when one follows the disciplic succession (evaṁ paramparā-prāptam imaṁ rājarṣayo viduḥ [Bg. 4.2]). Manufacturing many ways of chanting will never be effective. However, chanting the song or the narration left by the previous ācāryas (mahājano yena gataḥ sa panthāḥ [Cc. Madhya 17.186]) is extremely effective, and this process is very easy.
(Srimad Bhagavatam----7:9:18----purport).

The Supreme Personality of Godhead is the master of those who observe vows and austerities, and it is He who bestows benedictions upon them. He is worshipable for the devotee throughout the devotee's life, for He never breaks His promises. As He says in Bhagavad-gītā (9.31), kaunteya pratijānīhi na me bhaktaḥ praṇaśyati: "O son of Kuntī, declare it boldly that My devotee never perishes." The Lord is addressed here as acyuta, the infallible, because He takes care of His devotees. Anyone inimical to the devotees is certainly vanquished by the mercy of the Lord.
(Srimad Bhagavatam----8:17:8----purport).

“By chanting the holy name,” Lord Caitanya continued, “I became almost mad. However, after inquiring from My spiritual master I have come to the conclusion that instead of striving for achievement in the four principles of religiosity [dharma], economic development [artha], sense gratification [kāma] and liberation [mokṣa], it is better if somehow or other one develops transcendental love of Godhead. That is the greatest success in life. One who has attained love of Godhead chants and dances by his nature, not caring for the public.” This stage of life is known as bhāgavata-jīvana, or the life of a devotee.
(Sri Caitanya Caritamrta----1:7:95-96----purport).

The word hari has different meanings, of which two are foremost. Hari means that He takes away all inauspicious things from the devotee's life and that He attracts the mind of the devotee by awarding him transcendental love of Godhead. Kṛṣṇa is so attractive that anyone who can remember Him in some way or another becomes freed from the four kinds of material miseries. The Lord gives special attention to His devotee and banishes the devotee's various sinful activities, which are stumbling blocks for the advancement of devotional service. This is called routing the influence of ignorance. Simply by hearing about Him, one develops love for Him. That is the gift of the Lord. On one side He takes away inauspicious things, and on the other side He awards the most auspicious things. That is the meaning of hari.
(Teachings of Lord Caitanya).