The Messenger of Allah ﷺ said, "I have been commanded to fight people until they say there is no god but Allah. Once they say it, their lives and their wealth are protected from me, and their reckoning is with Allah."When Abu Bakr assumed leadership and some people apostatized, Abu Bakr resolved to fight them.Umar said, "How can you fight these people when they still pray?"Abu Bakr replied, "By Allah, I will fight anyone who separates the prayer from the zakat. By Allah, if they withheld from me even a young goat that they used to give to the Messenger of Allah ﷺ, I would fight them for it."Umar said, "When I saw that Allah had opened Abu Bakr's heart to fighting them, I knew it was the truth."
حدثنا روح حدثنا محمد بن أبي حفصة حدثنا الزهري عن عبيد الله بن عبد الله
قال رسول الله ﷺ أمرت أن أقاتل الناس حتى يقولوا لا إله إلا الله فإذا قالوها عصموا مني دماءهم وأموالهم وحسابهم على الله قال فلما قام أبو بكر وارتد من ارتد أراد أبو بكر قتالهم قال عمر كيف تقاتل هؤلاء القوم وهم يصلون قال فقال أبو بكر والله لأقاتلن قوما ارتدوا عن الزكاة والله لو منعوني عناقا مما فرض الله ورسوله لقاتلتهم قال عمر فلما رأيت الله شرح صدر أبي بكر لقتالهم عرفت أنه الحق
Its isnad is sahih, it passed at 10203, and Muhammad bin Abu Hafsa is truthful but makes mistakes, though his hadith here is sahih, and his hadith appears in the Sahihayn.