The Lord definitely says that no one is more dear to Him than one who is always engaged in the preaching work of the Lord's name and fame all over the world. The scientific discoveries of the material world can also be equally engaged in carrying out His order. He wants the message of the Bhagavad-gītā to be preached amongst His devotees.
(SRIMAD BHAGAVATAM-------1:5:36------PURPORT).

The Lord has declared openly in Bhagavad-gītā how He becomes pleased with us, and the same process is practically demonstrated in the life and preaching work of Lord Śrī Caitanya Mahāprabhu. The perfect process of performing yajñas, or sacrifice, to please the Supreme Lord Hari (the Personality of Godhead, who gets us free from all miseries of existence) is to follow the ways of Lord Śrī Caitanya Mahāprabhu in this dark age of quarrel and dissension.
(SRIMAD BHAGAVATAM-------1:12:34------PURPORT).

The first-class devotee does not at all see anyone who is not in the service of the Lord, but the second-class devotee makes distinctions between devotees and nondevotees. The second-class devotees are therefore meant for preaching work, and as referred to in the above verse, they must loudly preach the glories of the Lord. The second-class devotee accepts disciples from the section of third-class devotees or nondevotees. Sometimes the first-class devotee also comes down to the category of the second-class devotee forpreaching work.
(SRIMAD BHAGAVATAM-------1:3:21------PURPORT).

Not only were all the pure devotees like Nārada self-realized souls, but they were engaged in preaching work automatically by spiritual impetus, and thus they delivered many poor souls entangled in the material modes. They became so powerful because they sincerely followed the Bhāgavatam principles by regular hearing and worshiping. By such actions the accumulated material lusts, etc., become cleansed by the personal endeavor of the Lord within the heart. The Lord is always within the heart of the living being, but He becomes manifested by one's devotional service.
(SRIMAD BHAGAVATAM-------1:8:5------PURPORT).

One who is not a pure devotee of the Supreme Lord Kṛṣṇa is not completely cleansed in the heart. But a perfectly cleansed person never quits the devotional service of the Lord. In discharging such devotional service, as ordered by Brahmājī to Nārada in the preaching of Śrīmad-Bhāgavatam, sometimes a representative of the Lord engaged in preaching work meets various so-called difficulties. This was exhibited by Lord Nityānanda when He delivered the two fallen souls Jagāi and Mādhāi, and similarly Lord Jesus Christ was crucified by the nonbelievers.
(SRIMAD BHAGAVATAM-------2:8:6------PURPORT).

One person is advised to act in Kṛṣṇa consciousness by working in the Deities' room, another is advised to act in Kṛṣṇa consciousness by performing editorial work, another is advised to do preaching work, and another is advised to carry out Kṛṣṇa consciousness in the cooking department. There are different departments of activity in Kṛṣṇa consciousness, and a spiritual master, knowing the particular ability of a particular man, trains him in such a way that by his tendency to act he becomes perfect.
(SRIMAD BHAGAVATAM-------3:22:7------PURPORT).

Of course, there are two kinds of devotees of the Lord. One is called goṣṭhy-ānandī, which means those who are preachers and have many followers for preaching the glories of the Lord and who live among those many, many followers just to organize missionary activities. Other devotees are ātmānandī, or self-satisfied, and do not take the risk ofpreaching work. They remain, therefore, alone with God. In this classification was Kardama Muni.
(SRIMAD BHAGAVATAM-------3:24:34------PURPORT).

A devotee travels all over the country, from door to door, preaching, "Be Kṛṣṇa conscious. Be a devotee of Lord Kṛṣṇa. Don't spoil your life in simply fulfilling your animal propensities. Human life is meant for self-realization, or Kṛṣṇa consciousness." These are the preachings of a sādhu. He is not satisfied with his own liberation. He always thinks about others. He is the most compassionate personality towards all the fallen souls. One of his qualifications, therefore, is kāruṇika, great mercy to the fallen souls. While engaged inpreaching work, he has to meet with so many opposing elements, and therefore the sādhu, or devotee of the Lord, has to be very tolerant.
(SRIMAD BHAGAVATAM-------3:25:21------PURPORT).

To go to Badarī-nārāyaṇa one has to pass through Hardwar on the path to the Supreme Personality of Godhead. Similarly, there are other holy places of pilgrimage, such as Prayāga (Allahabad) and Mathurā, and the topmost of them all is Vṛndāvana. Unless one is very advanced in spiritual life, it is recommended that he live in such holy places and execute devotional service there. But an advanced devotee like Nārada Muni who is engaged in preaching work can serve the Supreme Lord anywhere. Sometimes he even goes to the hellish planets. Hellish conditions do not affect Nārada Muni because he is engaged in greatly responsible activities in devotional service.
(SRIMAD BHAGAVATAM-------4:8:42------PURPORT).

Thus the devotee, being frustrated in his repeated attempts at economic development, ultimately takes solid shelter under the lotus feet of the Lord. This kind of action may also be accepted as īśa-vidhvaṁ-sitāśiṣām, whereby the Lord destroys one's material opulences but enriches one in spiritual understanding. In the course of our preaching work, we sometimes see that materialistic persons come to us and offer their obeisances to take blessings, which means they want more and more material opulences. If such material opulences are checked, such persons are no longer interested in offering obeisances to the devotees. Such materialistic persons are always concerned about their economic development. They offer obeisances to saintly persons or the Supreme Lord and give something in charity for preaching work with a view that they will be rewarded with further economic development.
(SRIMAD BHAGAVATAM-------4:22:36------PURPORT).

All devotees are in the disciplic succession stemming from Nārada Muni because they worship the Deity according to Nārada Muni's direction, namely the Nārada-pañcarātra, or the pāñcarātrika-vidhi. A devotee follows the principles of pāñcarātrika-vidhi as well as bhāgavata-vidhi. Bhāgavata-vidhi includes preaching work—śravaṇaṁ kīrtanaṁ viṣṇoḥ (S.B.7:5:23)—the hearing and chanting of the glories of Lord Viṣṇu, the Supreme Personality of Godhead. The pāñcarātrika-vidhi includes arcanaṁ vandanaṁ dāsyaṁ sakhyam ātma-nivedanam. Because a devotee rigidly follows the instructions of Nārada Muni, he has no fear of old age, disease or death.
(SRIMAD BHAGAVATAM-------4:27:24------PURPORT).

There are two kinds of devotees. One is called goṣṭhānandī and the other bhajanānandī. The word bhajanānandī refers to the devotee who does not move, but remains in one place. Such a devotee is always engaged in the devotional service of the Lord. He chants the mahā-mantra as taught by many ācāryas and sometimes goes out forpreaching work. The goṣṭhānandī is one who desires to increase the number of devotees all over the world. He travels all over the world just to purify the world and the people residing in it.
(SRIMAD BHAGAVATAM-------4:30:35------PURPORT).

As bumblebees collect honey from many flowers, a little from each, so a sannyāsī should beg from door to door but not accept very much food from any particular house; he should collect a little bit from every house. This is called the bahūdaka stage. When a sannyāsī is still more experienced, he travels all over the world to preach the glories of Lord Vāsudeva. He is then known as parivrājakācārya. The sannyāsī reaches the paramahaṁsa stage when he finishes his preaching work and sits down in one place, strictly for the sake of advancing in spiritual life. An actual paramahaṁsa is one who completely controls his senses and engages in the unalloyed service of the Lord.
(SRIMAD BHAGAVATAM-------5:1:27------PURPORT).

In our preaching work also, we deal with so much property and money and so many books bought and sold, but because these dealings all pertain to the Kṛṣṇa consciousness movement, they should never be considered material.
(SRIMAD BHAGAVATAM-------5:16:3------PURPORT).

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