In many Purāṇas it is sometimes asserted that a demigod is elevated to such a high position that he is almost on an equal level with the Supreme Personality of Godhead, but the conclusion that Lord Viṣṇu is the Supreme Personality of Godhead is confirmed in every scripture. Lord Śiva is described in the Brahma-saṁhitā to be like curd or yogurt. Curd is not different from milk. Since milk is transformed into curd, in one sense curd is also milk. Similarly, Lord Śiva is in one sense the Supreme Personality of Godhead, but in another sense he is not, just as curd is milk although we have to distinguish between the two. These descriptions are in the Vedic literature.
(SRIMAD BHAGAVATAM------4:4:16------PURPORT).

Lord Caitanya Mahāprabhu adopted the mood of Lord Śiva, for He is Śiva also. According to the philosophy of acintya-bhedābheda-tattva, Lord Śiva is not different from Lord Viṣṇu, but still Lord Śiva is not Lord Viṣṇu, just as yogurt is nothing but milk and yet is not milk nevertheless. One cannot get the benefit of milk by drinking yogurt. Similarly, one cannot get salvation by worshiping Lord Śiva. If one wants salvation, one must worship Lord Viṣṇu. This is confirmed in the Bhagavad-gītā (9.4): mat-sthāni sarva-bhūtāni na cāhaṁ teṣv avasthitaḥ. Everything is resting on the Lord, for everything is His energy, yet He is not everywhere. Lord Caitanya's adopting the mood of Lord Śiva is not extraordinary, but one should not therefore think that by worshiping Lord Śiva one is worshiping Lord Caitanya. That would be a mistake.
(SRI CAITANYA CARITAMRTA------1:17:100------PURPORT).

Although Lord Brahmā had received very respectful obeisances from Lord Śiva, he knew that Lord Śiva was in a more exalted position than himself. Lord Śiva's position is described in Brahma-saṁhitā: there is no difference between Lord Viṣṇu and Lord Śiva in their original positions, but still Lord Śiva is different from Lord Viṣṇu. The example is given that the milk in yogurt is not different from the original milk from which it was made.
(SRIMAD BHAGAVATAM------4:6:42------PURPORT).

When a Vaiṣṇava visits the temple of a demigod, his vision of that demigod is different from the vision of the impersonalists and Māyāvādīs. The Brahma-saṁhitā supports this. A Vaiṣṇava's visit to the temple of Lord Śiva, for example, is different from a nondevotee's visit. The nondevotee considers the deity of Lord Śiva an imaginary form because he ultimately thinks that the Supreme Absolute Truth is void. However, a Vaiṣṇava sees Lord Śiva as being simultaneously one with and different from the Supreme Lord. In this regard, the example of milk and yogurt is given. Yogurt is actually nothing but milk, but at the same time it is not milk. It is simultaneously one with milk yet different from it.
(SRI CAITANYA CARITAMRTA------2:9:360------PURPORT).

Two words are very significant in this verse. Trayāṇām indicates "three," namely Lord Brahmā, Lord Śiva and Lord Viṣṇu. Bhidām means "different." They are three, and therefore they are separate, but at the same time they are one. This is the philosophy of simultaneous oneness and difference, which is called acintya-bhedābheda-tattva. The example given in the Brahma-saṁhitā is that milk and yogurt are simultaneously one and different; both are milk, but the yogurt has become changed. In order to achieve real peace, one should see everything and every living entity, including Lord Brahmā and Lord Śiva, as nondifferent from the Supreme Personality of Godhead. No one is independent. Every one of us is an expansion of the Supreme Personality of Godhead. This accounts for unity in diversity. There are diverse manifestations, but, at the same time, they are one in Viṣṇu. Everything is an expansion of Viṣṇu's energy.
(SRIMAD BHAGAVATAM------4:7:54------PURPORT).

The word svāṅga-viśeṣābhāsa-rūpe, indicating the form by which the Lord begets living entities in the material world, is explained herein. He is Lord Śiva. In the Brahma-saṁhitā it is stated that Lord Śiva, who is another form of Mahā-Viṣṇu, is like yogurt. Yogurt is nothing but milk, yet it is not milk. Similarly, Lord Śiva is considered the father of this universe, and material nature is considered the mother. The father and mother are known as Lord Śiva and goddess Durgā. Together, Lord Śiva's genitals and the vagina of goddess Durgā are worshiped as the śiva-liṅga. This is the origin of the material creation. Thus Lord Śiva's position is between that of the living entity and that of the Supreme Lord. In other words, Lord Śiva is neither the Supreme Personality of Godhead nor a living entity. He is the form through which the Supreme Lord works to beget living entities within this material world. As yogurt is prepared when milk is mixed with a culture, the form of Lord Śiva expands when the Supreme Personality of Godhead is in touch with material nature. The impregnation of material nature by the father, Lord Śiva, is wonderful because at one time innumerable living entities are conceived.
(SRI CAITANYA CARITAMRTA------2:20:273------PURPORT).

One who considers Lord Viṣṇu to be in the same category with devas like Lord Brahmā or Lord Śiva or who thinks Lord Brahmā and Śiva to be equal to Lord Viṣṇuis to be considered as pāṣaṇḍī (a faithless nonbeliever). Therefore in this verse Lord Viṣṇu is distinguished in the words namo viśuddha-sattvāya. Although a living entity like us, Lord Brahmā is exalted due to his pious activities; therefore he is given the high post of Brahmā. Lord Śiva is not actually like a living entity, but he is not the Supreme Personality of Godhead. His position is somewhere between Viṣṇu, the Supreme Personality of Godhead, and Brahmā, the living entity. Lord Śiva is therefore explained in Brahma-saṁhitā (5.45) in this way:
kṣīraṁ yathā dadhi vikāra-viśeṣa-yogāt
sañjāyate na hi tataḥ pṛthag asti hetoḥ
yaḥ śambhutām api tathā samupaiti kāryād
govindam ādi-puruṣaṁ tam ahaṁ bhajāmi
Lord Śiva is considered to be like yogurt (dadhi). Yogurt is nothing but transformed milk; nonetheless, yogurt cannot be accepted as milk. Similarly, Lord Śiva holds almost all the powers of Lord Viṣṇu, and he is also above the qualities of the living entity, but he is not exactly like Viṣṇu, just as yogurt, although transformed milk, is not exactly like milk.

(SRIMAD BHAGAVATAM------4:30:24------PURPORT).

Of the three deities supervising the creation, maintenance and dissolution of the universe, Lord Viṣṇu is never separate from the original Viṣṇu. However, Lord Śiva and Brahmā, due to their association with māyā, are different from Viṣṇu. Viṣṇu cannot be transformed into any form of material energy. Whenever there is association with māyā, the personality involved must be different from Lord Viṣṇu. Therefore Lord Śiva and Lord Brahmā are called guṇa-avatāras, for they associate with the material qualities. The conclusion is that Rudra is not exactly Lord Viṣṇu but rather a transformation of Viṣṇu. Therefore, he does not come within the category of the viṣṇu-tattvas. Thus he is inconceivably one with Viṣṇu and different from Him. The example given in this verse is very clear. Milk is compared to Viṣṇu. As soon as milk touches a sour substance, it becomes yogurt, or Lord Śiva. Although yogurt is constitutionally milk, it cannot be used in place of milk.

(SRI CAITANYA CARITAMRTA------2:20:309------PURPORT).

Lord Śiva is described in the Brahma-saṁhitā (5.45):
kṣīraṁ yathā dadhi vikāra-viśeṣa-yogāt
sañjāyate na hi tataḥ pṛthag asti hetoḥ
yaḥ śambhutām api tathā samupaiti kāryād
govindam ādi-puruṣaṁ tam ahaṁ bhajāmi
"Milk changes into yogurt when mixed with a yogurt culture, but actually yogurt is constitutionally nothing but milk. Similarly, Govinda, the Supreme Personality of Godhead, assumes the form of Lord Śiva for the special purpose of material transactions. I offer my obeisances at Lord Govinda's lotus feet." Lord Śiva is the Supreme Personality of Godhead in the same sense that yogurt is also milk although at the same time it is not milk. For the maintenance of the material world there are three incarnations—Brahmā, Viṣṇu and Maheśvara (Lord Śiva). LordŚiva is Viṣṇu in an incarnation for the mode of ignorance. The material world exists predominantly in the mode of ignorance. Therefore Lord Śiva is compared here to the longitude and latitude of the entire universe, which resembles a cloth woven of threads extending for both its length and breadth.

(SRIMAD BHAGAVATAM------9:9:7------PURPORT).

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