SB 4.20.12: Lord Viṣṇu told King Pṛthu: My dear King, the constant change of this material world is due to the interaction of the three modes of material nature. The five elements, the senses, the demigods who control the senses, as well as the mind, which is agitated by the spirit soul — all these taken together comprise the body. Since the spirit soul is completely different from this combination of gross and subtle material elements, My devotee who is connected with Me in intense friendship and affection, being completely in knowledge, is never agitated by material happiness and distress.
The question may be raised that if the living entity has to act as the superintendent of the activities of the bodily combination, then how can he be indifferent to the activities of the body? The answer is given here: these activities are completely different from the activities of the spirit soul of the living entity. A crude example can be given in this connection: A businessman riding in a motorcar sits in the car, supervises its running and advises the driver. He knows how much gasoline is used up, and he knows everything about the car, but still he is apart from the car and is more concerned with his business. Even while riding in the car, he thinks of his business and his office. He has no connection with the car, although he is sitting there. As the businessman is always absorbed in thoughts of his business, so the living entity can be absorbed in thoughts of rendering loving service to the Lord. Then it will be possible to remain separate from the activities of the material body. This position of neutrality can be possible only for a devotee.
The word baddha-sauhṛdāḥ, "bound in friendship," is particularly used here. Karmīs, jñānīs and yogīs cannot be bound in devotional service. Karmīs fully engage in the activities of the body. Their aim of life is to give comfort to the body only. Jñānīs try to get out of entanglement by philosophical speculation, but they have no standing in the liberated position. Because they do not take shelter under the lotus feet of the Lord, they fall down from the exalted position of Brahman realization. Yogīs also have a bodily concept of life — they think that they can achieve something spiritual by exercising the body through dhāraṇā, āsana, prāṇāyāma, etc. A devotee's position is always transcendental because of his intimate relationship with the Supreme Personality of Godhead. Therefore, to remain always aloof from the actions and reactions of the body and engage in one's real occupation, namely rendering service to the Lord, can be possible only for devotees.