Tawheed is the central theme of the teachings of prophet Muhammad (peace be upon him) that the
Muslims must worship the Almighty Allah alone and discard all the polytheistic activities or symptoms of shirk.

The Prophet stayed in Makkah for thirteen years, calling for the worship of Allah alone, in secret then openly, when Allah commanded him to proclaim the truth. So he called them in a gentle and kind manner, without fighting. He called his clan and closest relatives, then he warned his people and those around them, then he warned all the Arabs, then he warned all of mankind. Then Allah said: 

“Therefore proclaim openly (Allah's Message Islamic Monotheism) that which you are commanded, and turn away from Al Mushrikun (polytheists, idolaters, and disbelievers)” [al-Hijr 15:94]

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