Which was revealed in Makkah

The Virtues of Surat Az-Zumar

An-Nasa'i recorded that `A'ishah, may Allah be pleased with her, said, "The Messenger of Allah ﷺ used to fast until we would say, `He does not want to break fast,' and he would not fast until we would say, `He does not want to fast.' And he used to recite Bani Isra'il Al-Isra' and Az-Zumar every night."

Commentary

In verse 2, it was said: فَاعْبُدِ اللَّـهَ مُخْلِصًا لَّهُ الدِّينَ أَلَا لِلَّـهِ الدِّينُ الْخَالِصُ - (so worship Allah in submission to Him exclusively. Remember, Allah alone deserves the exclusive submission.). The word: دِین (deen) at this place means worship, submission, devotion or obedience which is inclusive of adhering to all religious injunctions. In the first statement earlier to this, the address was to the Holy Prophet ﷺ where he was commanded to make the worship of and obedience to Allah sincere and exclusive for Him, so as there remains no trace of shirk or of any hypocrisy or false pretension. The second statement is to emphasize the first statement in that sincerity in worship is the exclusive right of Allah and no one else, other than Him deserves it.