Firstly Lord Shiva does not exist only at one level. He exists at different levels of reality.
So there is Sadashiva, who Jiva Goswami describes in Brahma samhita that his abode is almost in the spiritual world. It is one fourth in the spiritual world, three fourth in the material world. That abode is eternal and there are his devotees who treat him not as God but as a great devotee and together they glorify Lord Vishnu eternally. That is the eternal abode at the border of the material and spiritual worlds but it is eternal. That Shiva is greater than everyone else and all the other devtas because that Shiva is eternal. Even Brahma or Indra, none of the other devtas have any counterpart like that.
Now within the material world we have Brahmaji as first created being. So he is the first created being and from him there is the manifestation of Shiva, he was born when he gets angry, the kumaras are not procreating, so the anger manifests and there is Rudra. So this is the manifestation of that Shiva coming over here. That Shiva manifest through Brahmaji. That Sadashiva is eternal, this Shiva is not eternal. Just as Brahma himself is not eternal. Just as this Brahma is meant for this universe, similarly this manifestation of Rudra is meant for this universe. Then that Rudra starts reproducing and then Brahmaji become little scared that he is so angry he will reproduce creatures like him only. So better you go and perform austerities. Then later on the process of creation this Rudra expands into more rudras. The multiple Rudras are there, they come from the Rudra, they come from this Shiva who has come from Brahmaji. So within the universe Shiva is the son of Brahmaji.
Beyond this there is Shiva who is the destructive principle. Three principle, when we talk about Brahma, Vishnu, Mahesh, they are three God’s , we are just not referring to three person. They are three person , no doubt but they are also referring to three principles. Three principles are creation, maintenance, destruction. These are also connected with three modes. Goodness is maintenance, passion is creation and ignorance is destruction. We know that Sadashiva is eternal and he has his consort Parvati devi who also with him lives eternally. But in the material world it is also said at many times that Shiva is touched by mode of ignorance, that’s why he is kṣīraṁ yathā dadhi vikāra-viśeṣa-yogāt. Milk touched with some acid, gets transform in curd and like that Vishnu gets transformed into Shiva. This does not refer to Sadashiva. Sadashiva is almost transcendental because he is also in the spiritual world, nothing destruction happening over there. But in this world these three devtas– Brahama, Vishnu, Mahesh are in one sense under prakarti. They all under prakarti because they are all within prakarti, within material nature there. Although they are not conditioned like us to the same extent but they are to some extent under material nature, not under in sense of being imprisonment but they are influencable by material nature to a small degree. When we talk about Vishnu, Prabhupada talks about in two ways and one of two places Prabhupada says that Vishnu is not definitely like the other Gods. He is transcendental but the fact is if you look at the purshaavtars, the pursha avtars are Mahavishnu, garbhodakshayi Vishnu and khsirodakshaye Vishnu. Vishnu is not directly in contact with material nature. He is transcendental but certainly the Vishnu who is maintaining the material world or is connected with the maintenance of the material world is much more in contact with material world than Krishna in spiritual world or even Vishnu in Vaikuntha. That’s how these avtars of Vishnu who were in contact with material world they are called purusha avtars. Purusha is normally defined in contrast with prakarti. Purusha in and of itself is always like a pair with prakarti. So purusha avtars refers to those avtars which are connected with prakarti. Now we are not saying that they are controlled by prakarit. but they are in contact with prakarti. Spiritual world avtars manifestation are not connected with prakarti at all.
This feature of creation, maintenance, destruction, it is innate to material nature. It’s constantly happening and that is done by these particular devtas, Vishnu maintains or Shiva destroys. Now off course Lord Shiva role becomes most dramatic and dominant at the end of creation when everything has to be destroyed. But throughout the destruction that is happening ultimately supervise by Lord Shiva only in this world. That’s why the same verse which is used,
nārāyaṇaḥ paro devas tasmāj jātaś caturmukhaḥ tasmād rudro ’bhavad devaḥ sa ca sarva-jñatāṁ gataḥ
one of the verse which Prabhupada quotes in 10.8 purport, there he says that after Shiva is born from Brahmaji sarva-jnatam, he becomes all knowing. So all knowing there is absolute omniscience and there is partial omniscience. Partial omniscience means that for the sake of their functioning in this world Brahmaji, Shivaji and Yamraja, they are given omniscience of this universe. Krishna has omniscience of all the universes but they are given omniscience of this universe and that’s how they bring about the destruction, whatever is required or Yamraja gives sinful punishments. Punishment for sinful reactions and Brahmaji overall looks management in the universe.
In this way we say that Shiva exists eternally in spiritual world. When Shiva manifest through Brahmaji and in that manifest multiple Shivas. Then eleven Rudras come after that. Now again Shiva if we see there is Kailash parvat on the Himalayas. But look at the Bhagavatam there is description of Kailash which is much-much bigger. That means Kailash is in the heavenly planets also. Just like Goloka Vrindavan in the spiritual world, there is replica Vrindavan over here. Similarly there is a replica of Kailash in the Himalayas. But along with that there is a celestial Kailash that is there in the heavenly planets. That Shiva is not Sadashiva. He is in the material world and he is not like the other Gods. Other Gods they change after manvantara. The eighth canto fourteenth chapter talks about it. He was Indra, he was this, he was that, like that but this does not change. Shiva exists almost like as long as the universe exists. Then Shiva destroy universe and Brahmaji also dies and that Shiva manifesting also ends, Sadashiva continues to exists. Thats how there is a connection between three. Now depending on what we are referring to the Mahesh what we talking about will be different. Mahesh will be destructive influence. Normally it refer to the principle of destruction that is Shiva. So within the universe it is the specific Shiva who brings about destruction. Overall in each universe there is a particular Shiva who does that. But overall we understand this is the power of Sadashiva, that is manifesting in this world through some of his expansions through whom the destruction happens.
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