I posted the information for you. I referred you to the scripture for it in the Qur'an. What's your problem?
It seems that the Muslims do not have any Sabbath days. They call their Friday prayer, adhan, not Sabbath, to their god, Allah.
If you were to believe in a god, be sure that He is the true God. How do we know the true God? It is easy, plain, and simple. And logical too. Not only is He omnipotent and omnipresent, He is omniscient. That means He knows everything, including what happened in the past and what will happen in the future.