According to Vedic instructions, one should understand the constitutional position of the living entity, the position of the Lord, the position of material energy, and their interrelations. First of all, one should try to understand the constitutional position of the Supreme Lord, the Personality of Godhead. The Supreme Personality of Godhead has an eternal, cognizant, blissful body, and His spiritual energy is distributed as eternity, knowledge and bliss. In His blissful identity can be found His pleasure potency, in His eternal identity He is the cause of everything, and in His cognizant identity He is the supreme knowledge. Indeed, the word kṛṣṇa indicates that supreme knowledge. In other words, the Supreme Personality, Kṛṣṇa, is the reservoir of all knowledge, all pleasure and all eternity. The supreme knowledge of Kṛṣṇa is exhibited in three different energies—internal, marginal and external. By virtue of His internal energy He exists in Himself with His spiritual paraphernalia, by means of His marginal energy He exhibits Himself as the living entities, and by means of His external energy He exhibits Himself as the material world. Behind each and every exhibition of energy there is the background of eternity, His pleasure potency and His cognizance potency.
The conditioned soul is the marginal potency overpowered by the external potency. However, when the marginal potency comes under the influence of the spiritual potency, it becomes eligible for love of Godhead. The Supreme Lord enjoys six kinds of opulences, and no one can establish that He is formless or that He is without energy. If someone claims so, his contention is completely opposed to the Vedic instructions. Actually, the Supreme Personality of Godhead is the master of all energies. The living entity, however, being His infinitesimal part and parcel, can be overpowered by the material energy.
In the Muṇḍaka Upaniṣad it is stated that two birds are sitting on the same tree. One of them is eating the fruit of the tree, while the other is not eating but simply witnessing the activities of the first bird. Only when the bird eating the fruit looks at the other bird does he become free from all anxieties. This is the position of the infinitesimal living entity. As long as he is forgetful of the Supreme Personality of Godhead, he is subjected to the threefold miseries. But when he looks toward the Supreme Lord and becomes the Lord's devotee, he becomes free from all anxieties and miseries of material existence. The living entity is eternally subordinate to the Supreme Lord: the Supreme Lord is always the master of all energies, whereas the living entity is always under the control of the Lord's energies. Being qualitatively one with the Supreme Lord, the living entity has the tendency to try to lord it over the material nature; however, being infinitesimal, he is then controlled by the material nature. Thus the living entity is called the marginal potency of the Lord.