The command to fight the people until they say "La ilaha illallah Muhammad Rasul-Allah", and establish Salat, and pay the Zakat, and believe in everything that the prophet (ﷺ) brought. Whoever does that, his life and his wealth are protected except by its right, and his secrets are entrusted to Allah, the most high. Fighting those who withhold Zakat or other than that is one of the duties of Islam and the Iman should be concerned with the Laws of Islam
حَدَّثَنَا شَيْبَانُ بْنُ فَرُّوخَ، حَدَّثَنَا عَبْدُ الْوَارِثِ، عَنْ عَبْدِ اللَّهِ بْنِ سَوَادَةَ الْقُشَيْرِيِّ، حَدَّثَنِي وَالِدِي، أَنَّهُ سَمِعَ سَمُرَةَ بْنَ جُنْدُبٍ، يَقُولُ سَمِعْتُ مُحَمَّدًا، صلى الله عليه وسلم يَقُولُ
Samura b. Jandub reported Muhammad (ﷺ) as saying. The call of Bilal may not mislead any one of you (and he may, under the wrong impression gathered from it, refrain) from taking meal before the commencement of the fast (for the streaks) of this whiteness (which are vertical indicate the false dawn and the true dawn with which the fast commences is that when the streaks of light are) spread.
Reference: Sahih Muslim 1094 a In-book : Book 13, Hadith 50 USC-MSA web (English) : Book 6, Hadith 2407 (deprecated)
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