After the Prophet ﷺ died in 11 AH, many Arab tribes turned back — some rejecting Islam outright, some following false prophets such as Musaylimah, and others refusing to pay the zakāt while claiming to remain Muslim. Abū Bakr aṣ-Ṣiddīq resolved to fight them, famously declaring, "By Allah, I will fight whoever separates prayer and zakat, for zakat is the obligatory due upon wealth" (Sahih al-Bukhari 1400; Sahih Muslim 20). ʿUmar, who had at first hesitated, later recognized that Allah had opened Abū Bakr's heart to the truth. His firm stand preserved the unity of the ummah and the authority of its obligations, securing Arabia and paving the way for the later conquests.
Evidence — the daleel
Sahih al-Bukhari 1400 ṢaḥīḥSahih Muslim 20 Ṣaḥīḥ
On deen2u
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.