The term "Shaivite" is overused nowadays. For instance, Iyer Brahmins are often called Shaivites, but they're actually followers of Adi Shankaracharya's Smartha sect (as I discuss here and here) and simply adopt Shiva as their Ishta Devata. True philosophical Shaivism is relatively rare nowadays (in contrast to philosophical Vaishnavism which is pretty common). I discussed one genuine Shaivite sect, the Lingayat sect of Basava, in my answer here. But my question is about a more famous sect of Shaivism, known as Shaiva Siddhanta.
Just as the Sri Vaishnava sect is based on the Pancharatra Agamas and the poems of the 12 Alwars, Shaiva Siddhanta is based on the Shaiva Agamas and the poems of the 63 Nayanars. Now as I discuss this question, the vast majority of Hindus belong to the Vedanta school, which is based on the Brahma Sutras, a work by the sage Vyasa which summarizes and systematizes the philosophical teachings of the Upanishads. But the Shaiva Siddhanta sect has a complicated relation with Vedanta. Some Shaiva Siddhantins subscribe to the Vedanta school; in my question here I discuss the Srikantha Bhashya, a Shaiva Siddhanta commentary on the Brahma Sutras. But in this answer I found out that the Saiva Siddhanta Church, a large Shaiva Siddhanta organization, does not subscribe to the Vedanta school.
In any case, page 25 of the book "Collected Lectures on Saiva Siddhanta" discusses the ambivalent feelings that the Shaiva Siddhanta sect has to the Brahma Sutras:
Saiva-Siddhantins do not attach the greatest importance to the Brahma Sutras. They are just as important with respect to the Upanishads or Vedanta as Purva Mimamsa or Jaimini Sutras are with respect to the Vedas. They attach the greatest importance to the Sivajnana Bodha Sutras that are, in their opinion, faultless and all comprehensive. Further, they see some of the Vyasasutras contradictory to the express sayings of the Upanishads ; for example, the Sutra, 'Parinamat' is contradictory to the Upanishadic text "Mayantu Prakritim Vidyat Mayinantu Mahesvaram". But still they follow the commentary of Sri Kantacharya on the Brahma Sutras.
Now "Parinamat" refers to Adhyaya 1 Pada 4 Sutra 27 of the Brahma Sutras, and it means "because of transformation". The context of this is the fundamental tenet of the Vedanta school that Brahman is both the material cause and the efficient cause of the Universe, i.e. Brahman is both the substance the Universe is made of and the operator of the Universe. And this Sutra is talking about Brahman's transformation into the Universe; see this section of Adi Shankaracharya's commentary and this section of Ramanujacharya's commentary.
Now as I discuss in question, the notion of the Universe being made of Brahman is contrary to the beliefs of traditional Shaivites that Pashupati or Shiva is the operator of the Universe but not the material cause. So it's not surprising that some Shaiva Siddhantins would dispute this Sutra. But my question is about the quote they use to try to refute the Sutra. It comes from chapter 4 verse 10 of the Shwetashwatara Upanishad:
māyāṃ tu prakṛtiṃ vidyānmāyinaṃ ca maheśvaram ।
tasyavayavabhūtaistu vyāptaṃ sarvamidaṃ jagat ॥
Know then Prakriti (nature) is Mâyâ (art), and the great Lord the Mâyin (maker); the whole world is filled with what are his members.
My question is, why do Shaiva Siddhantins believe that this Shwetashwatara Upanishad quote contradicts the Brahma Sutras' claim of Brahman transforming into the Universe? Is it because matter is called "Maya" and Brahman is called "Mayin", so they think the two have to be completely separate? Because I don't see why "Mayin" can't transform into "Maya". Or is there some other reason?
I would note that in Srikantha's Shaiva Siddhanta commentary on the Brahma Sutras, he uses this same quote as evidence in favor of Brahman being the material cause. See this excerpt from the Srikantha Bhashya:
The shruti says, "Know verily Maya as Prakriti and Mayin (the possessor of Maya) the Maheshvara. By that which forms his limb is all this universe pervaded." From this we learn that Maya is the Prakriti (material cause) of all, [and] that Maheshvara is the being endured with it.... Thus ... the Prakriti of all creatures is the Parameshvara himself.
So it seems that two groups of Shaiva Siddhantins view the same Shwetashawatara Upanishad quote as evidence for and against the exact same Sutra!
In any case, does anyone know of other Shaiva Siddhanta works which discuss why this quote is viewed as contradicting the notion of Brahman being the material cause?