Answer
Salam (Peace) Graeme,
Thank you for contacting About Islam with your question.
First, I would like to correct an error in your question: The Ka`bah is not the Black Stone.
In the Arabic language ka`bah literally means cube. The Ka`bah is the cubic structure built out of stone blocks at the center of the Sacred Mosque in Makkah.
It was originally built by Prophet Abraham (Ibrahim) and his son Ishmael (Isma`il) (peace be upon them both).
It is believed that the Ka`bah was erected at the original site of a sanctuary established by the first Prophet, Adam (peace be upon him-PBUH).
Embedded in the corner of the structure is Al-Hajar Al-Aswad, or the Black Stone, which is believed to be a meteorite.
This stone is the only surviving object from the original building, but it has never been worshiped and it has no special sanctity or power.
If any feeling akin to worship is directed towards the Black Stone of the Ka`bah by the pilgrim, the very purpose of his/her pilgrimage is undermined because Islam is vehement in its opposition to all forms of idolatry and categorical in its teaching that God alone deserves worship.
Over the years, the message of Abraham was forgotten and the Ka`bah was filled with idols until Muhammad (PBUH) cleansed it from all idols and vestiges of idolatry at the time of the peaceful re-conquest of Makkah.
Henceforth, pilgrimage to the Ka`bah was made obligatory for all capable Muslims at least once in a lifetime.
The Ka`bah is significant, not because of its physical structure or material, but because it was declared as a symbol of the worship of the One God by God Himself, through His Prophet Abraham (PBUH).
There is no idol in the Ka`bah; inside it there is nothing at all, period.
The idea that the idol of Shiva (one of the Hindu gods) is in the Ka`bah is a completely wrong. Maybe it was spread by some Hindu fanatics, trying to stake a claim in the Ka`bah as one of their own temples of the past.
There is no idol of Shiva or Shiva Ling (the phallic symbol of Shiva, worshiped by the Hindus) or of the crescent moon inside, outside, or anywhere near the Ka`bah.
Your second question is about pantheism:
Pantheism is the philosophy that everything is God (pan=everything, theos=God) or that the universe and nature are divine.
For all practical purposes, according to Islam, pantheism is atheism because it does not acknowledge the existence of God apart from the world, nor does it say that there is a God Who is the Creator and Sustainer of the universe, nor does it say that there is divine judgment or the hereafter.
From this it is clear that pantheism cannot have any place in Islam.
It is true that Islam gives 99 names to God. But this does not mean that God can take 99 forms. These names signify the qualities of the One God, such as the Creator, the Sustainer, the Merciful, the Forgiving.
And they do not in any way mean that God takes different forms or incarnates in those forms. The polytheists or those who believe in the incarnations of God may try to misinterpret the significance of the names of God to find some justification for their false beliefs.
But from the point of view of the Quran and the Sunnah (the prophetic tradition), there is no chance for such misinterpretation. Most assuredly, they are wrong. And Allah knows best.
Thank you again for your question and please keep in touch.
Salam.
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