The mind is always flying to this and that, but one must practice concentrating the mind always on the form of the Supreme Lord, Śrī Kṛṣṇa, or on the sound of His name. The mind is naturally restless, going hither and thither, but it can rest in the sound vibration of Kṛṣṇa. One must thus meditate on paramaṁ puruṣam, the Supreme Personality of Godhead in the spiritual kingdom, the spiritual sky, and thus attain Him. The ways and the means for ultimate realization, ultimate attainment, are stated in the Bhagavad-gītā, and the doors of this knowledge are open for everyone. No one is barred out. All classes of men can approach Lord Kṛṣṇa by thinking of Him, for hearing and thinking of Him is possible for everyone.
(BHAGAVAD-GITA-------INTRODUCTION).

Kṛṣṇa tells Arjuna that he should act in yoga. And what is that yoga? Yoga means to concentrate the mind upon the Supreme by controlling the ever-disturbing senses. And who is the Supreme? The Supreme is the Lord. And because He Himself is telling Arjuna to fight, Arjuna has nothing to do with the results of the fight. Gain or victory are Kṛṣṇa's concern; Arjuna is simply advised to act according to the dictation of Kṛṣṇa. The following of Kṛṣṇa's dictation is real yoga, and this is practiced in the process called Kṛṣṇa consciousness. By Kṛṣṇa consciousness only can one give up the sense of proprietorship. One has to become the servant of Kṛṣṇa, or the servant of the servant of Kṛṣṇa (CC.2:13:80). That is the right way to discharge duty in Kṛṣṇa consciousness, which alone can help one to act in yoga.
(BHAGAVAD-GITA-----2:48------PURPORT).

Kṛṣṇa is realized in different degrees as Brahman, Paramātmā and the Supreme Personality of Godhead. Kṛṣṇa consciousness means, concisely, to be always engaged in the transcendental loving service of the Lord. But those who are attached to the impersonal Brahman or the localized Supersoul are also partially Kṛṣṇa conscious, because impersonal Brahman is the spiritual ray of Kṛṣṇa and Supersoul is the all-pervading partial expansion of Kṛṣṇa. Thus the impersonalist and the meditator are also indirectly Kṛṣṇa conscious. A directly Kṛṣṇa conscious person is the topmost transcendentalist because such a devotee knows what is meant by Brahman and Paramātmā. His knowledge of the Absolute Truth is perfect, whereas the impersonalist and the meditative yogī are imperfectly Kṛṣṇa conscious.

Nevertheless, all of these are instructed herewith to be constantly engaged in their particular pursuits so that they may come to the highest perfection sooner or later. The first business of a transcendentalist is to keep the mind always on Kṛṣṇa. One should always think of Kṛṣṇa and not forget Him even for a moment. Concentration of the mind on the Supreme is called samādhi, or trance. In order to concentrate the mind, one should always remain in seclusion and avoid disturbance by external objects. He should be very careful to accept favorable and reject unfavorable conditions that affect his realization. And, in perfect determination, he should not hanker after unnecessary material things that entangle him by feelings of possessiveness.

All these perfections and precautions are perfectly executed when one is directly in Kṛṣṇa consciousness, because direct Kṛṣṇa consciousness means self-abnegation, wherein there is very little chance for material possessiveness.

(BHAGAVAD-GITA-----6:10------PURPORT).

In the first six chapters of Bhagavad-gītā, the living entity has been described as nonmaterial spirit soul capable of elevating himself to self-realization by different types of yogas. At the end of the Sixth Chapter, it has been clearly stated that the steady concentration of the mind upon Kṛṣṇa, or in other words Kṛṣṇa consciousness, is the highest form of all yoga. By concentrating one's mind upon Kṛṣṇa, one is able to know the Absolute Truth completely, but not otherwise. Impersonal brahmajyoti or localized Paramātmā realization is not perfect knowledge of the Absolute Truth, because it is partial. Full and scientific knowledge is Kṛṣṇa, and everything is revealed to the person in Kṛṣṇa consciousness. In complete Kṛṣṇa consciousness one knows that Kṛṣṇa is ultimate knowledge beyond any doubts. Different types of yoga are only steppingstones on the path of Kṛṣṇa consciousness. One who takes directly to Kṛṣṇa consciousness automatically knows about brahmajyoti and Paramātmā in full. By practice of Kṛṣṇa consciousness yoga, one can know everything in full—namely the Absolute Truth, the living entities, the material nature, and their manifestations with paraphernalia.

(BHAGAVAD-GITA-----7:1------PURPORT).

Uddhava was standing near, and he heard Rādhārāṇī talking in this way, as if She had become almost mad for Kṛṣṇa. He was exceedingly surprised at how the gopīs were accustomed to thinking of Kṛṣṇa constantly in that topmost ecstasy of mahā-bhāva love. He had brought a message in writing from Kṛṣṇa, and now he wanted to present it before the gopīs, just to pacify them. He said, "My dear gopīs, your mission of human life is now successful. You are all wonderful devotees of the Supreme Personality of Godhead; therefore you are eligible to be worshiped by all kinds of people. You are worshipable throughout the three worlds because your minds are wonderfully absorbed in the thought of Vāsudeva, Kṛṣṇa. He is the goal of all pious activities and ritualistic performances, such as giving charity, rigidly following the austerity of vows, undergoing severe penances and igniting the fire of sacrifice. He is the purpose behind chanting different mantras, reading the Vedas, controlling the senses and concentrating the mind in meditation". These are some of the many different processes for self-realization and attainment of perfection of life. But actually they are meant only for realizing Kṛṣṇa and dovetailing oneself in the transcendental loving service of the Supreme Personality of Godhead.

(KRSNA BOOK).

One should concentrate his mind upon the Supreme Personality of Godhead, who alone distributes Himself in so many manifestations just as ordinary persons create thousands of manifestations in dreams. One must concentrate the mind on Him, the only all-blissful Absolute Truth. Otherwise one will be misled and will cause his own degradation.
In this verse, the process of devotional service is indicated by the great Gosvāmī, Śrīla Śukadeva. He tries to impress upon us that instead of diverting our attention to several branches of self-realization, we should concentrate upon the Supreme Personality of Godhead as the supreme object of realization, worship and devotion.

(SRIMAD BHAGAVATAM-------2:1:39--------TRANSLATION AND PURPORT).

The personified Vedas continued: "Dear Lord, there are many mystic yogīs who are very learned and deliberate in achieving the highest perfection of life. They engage themselves in the yogic process of controlling the life-air within the body. Concentrating the mind upon the form of Viṣṇu and controlling the senses very rigidly, they practice the yoga system, but even after much laborious austerity, penance and regulation, they achieve the same destination as persons inimical toward You. In other words, both the yogīs and the great, wise philosophical speculators ultimately attain the impersonal Brahman effulgence, which is automatically attained by the demons who are regular enemies of the Lord. Demons like Kaṁsa, Śiśupāla and Dantavakra also attain the Brahman effulgence because they constantly meditate upon the Supreme Personality of Godhead out of enmity. The real point is toconcentrate the mind on the Supreme Personality of Godhead. Women such as the gopīs were attached to Kṛṣṇa, being captivated by His beauty, and their mental concentration on Kṛṣṇa was provoked by lust. They wanted to be embraced by the arms of Kṛṣṇa, which resemble the beautiful round shape of a snake. Similarly, we, the Vedic hymns, simply concentrate our minds on the lotus feet of Your Lordship. Women like the gopīs concentrate upon You under the dictation of lust, and we concentrate upon Your lotus feet to go back home, back to Godhead. Your enemies also concentrate upon You, thinking always of how to kill You, and yogīs undertake great penances and austerities just to attain Your impersonal effulgence. All these different persons, although concentrating their minds in different ways, achieve spiritual perfection according to their different perspectives because You, O Lord, are equal to all Your devotees."

(KRSNA BOOK).

In meditation, there are two systems of yoga, namely aṣṭāṅga-yoga and sāṅkhya-yoga. Aṣṭāṅga-yoga is practice in concentrating the mind, releasing oneself from all engagements by the regulative processes of meditation, concentration, sitting postures, blocking the movements of the internal circulation of air, etc. Sāṅkhya-yoga is meant to distinguish the truth from ephemerals. But ultimately both the systems are meant for realizing the impersonal Brahman, which is but a partial representation of Nārāyaṇa, the Personality of Godhead. As we have explained before, the impersonal Brahman effulgence is only a part of the Personality of Godhead. Impersonal Brahman is situated on the person of the Supreme Personality of Godhead, and as such, Brahman is the glorification of the personality of the Godhead.

(SRIMAD BHAGAVATAM-------2:5:16--------PURPORT).

Samādhi involves concentrating the mind upon the supreme cause of all, even if one is unaware of whether His actual nature is personal, impersonal or localized. Concentration of the mind on the Supreme is certainly a form of devotional service. To cease from personal sense endeavors and to concentrate on the supreme cause is a sign of self-surrender, and when self-surrender is present, that is a sure sign of devotional service. Each and every living entity needs to engage in devotional service to the Lord if he wishes to understand the ultimate cause of his existence.

(SRIMAD BHAGAVATAM-------3:8:21--------PURPORT).

A conditioned soul is under the influence of mental speculation. However great one may be in the estimation of mundane education and learning, he cannot be free from the influence of psychic activities. Therefore it is very difficult to give up lust and the desires for low activities until one is in the line of devotional service to the Lord. When one is frustrated in lust and low desires, anger is generated from the mind and expressed from between the eyebrows. Ordinary men are therefore advised to concentrate the mind by focusing on the place between the eyebrows, whereas the devotees of the Lord are already practiced to place the Supreme Personality of Godhead on the seat of their minds. The theory of becoming desireless is untenable because the mind cannot be made desireless. When it is recommended that one be desireless, it is understood that one should not desire things which are destructive to spiritual values.

(SRIMAD BHAGAVATAM-------3:12:26--------PURPORT).

When one is detached from the attraction of material prosperity, one can actually concentrate his mind upon the Supersoul. As long as the mind is distracted towards the material, there is no possibility of concentrating one's mind and intelligence upon the Supreme Personality of Godhead or His partial representation, Supersoul. In other words, one cannot concentrate one's mind and energy upon the Supreme unless one is detached from the material world. Following detachment from the material world, one can actually attain transcendental knowledge of the Absolute Truth.
(SRIMAD BHAGAVATAM-------3:26:72--------PURPORT).

Cultivating Kṛṣṇa consciousness in Vṛndāvana is the best means of being liberated from material bondage, for in Vṛndāvana one can automatically meditate upon Kṛṣṇa. Vṛndāvana has many temples, and in one or more of these temples one may see the form of the Supreme Lord as Rādhā-Kṛṣṇa or Kṛṣṇa-Balarāma and meditate upon this form. As expressed here by the words brahmaṇy adhyāya, one should concentrate one's mind upon the Supreme Lord, Parabrahman. This Parabrahman is Kṛṣṇa, as confirmed by Arjuna in Bhagavad-gītā (paraṁ brahma paraṁ dhāma pavitraṁ paramaṁ bhavān (B.G.10:12). Kṛṣṇa and His abode, Vṛndāvana, are not different. Śrī Caitanya Mahāprabhu said, ārādhyo bhagavān vrajeśa-tanayas tad-dhāma vṛndāvanam. Vṛndāvana is as good as Kṛṣṇa. Therefore, if one somehow or other gets the opportunity to live in Vṛndāvana, and if one is not a pretender but simply lives in Vṛndāvana and concentrates his mind upon Kṛṣṇa, one is liberated from material bondage.
(SRIMAD BHAGAVATAM-------9:19:19--------PURPORT).

Nārada advises Dhruva to meditate on the pastimes of the Lord, which is as good as the meditation of concentrating one's mind on the form of the Lord. As meditation on any form of the Lord is valuable, so is chanting of different names of the Lord, such as Hari, Govinda and Nārāyaṇa. But in this age we are especially advised to chant the Hare Kṛṣṇa mantra as enunciated in the śāstra: Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare.
(SRIMAD BHAGAVATAM-------4:8:57--------PURPORT).

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