What does it represent? And why do millions of Muslims go around the Kaaba touching it?

Inside the silver casing is the black stone of kabba a meteoroid that fell from the sky

The Persian Shiite militias once attacked Mecca and stole the stone and also broke it and after recovery of it by the Saudi ruling house it was enclosed in the silver casing and placed back in the center of kabba

Kabba was believed to be the old dwelling place of the Gods (Alliens)

And contrary to the believe that the Muslim owns the black stone, it dates back thousands of years before Prophet Muhammad SAW was born , however during the Jihad and Mohammed SAW was destroying idols all accross the Arab kingdoms Allah specifically told him never to touch the stone of Kabbah


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Read about the stone of Diana in Ephesus...

Deep things dey and many are blind

https://amara.org/videos/AufCVBVSgwXm/en/884495/