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Aashura

What is the significance of the day of Aashura? Is fasting on 10th of Muharram alone permitted?

Surah at-Tawbah ayat 33

What is the meaning of the ayah?

يُرِيدُونَ أَن يُطْفِئُوا نُورَ اللَّهِ بِأَفْوَاهِهِمْ وَيَأْبَى اللَّهُ إِلَّا أَن يُتِمَّ نُورَهُ وَلَوْ كَرِهَ الْكَافِرُونَ – 9:32

هُوَ الَّذِي أَرْسَلَ رَسُولَهُ بِالْهُدَىٰ وَدِينِ الْحَقِّ لِيُظْهِرَهُ عَلَى الدِّينِ كُلِّهِ وَلَوْ كَرِهَ الْمُشْرِكُونَ – 9:33

Surah Kahf

What is the central theme of this Surah? Why is it recommended to ward off the ultimate trial of ad-Dajjal (the anti-Christ)?