When Allâh's Messenger (ﷺ) died and Bakr became the caliph some Arabs renegaded (converted to disbelief) (Bakr decided to declare war against them), 'Umar said to Abu Bakr, "How can you fight with these people although Allâh's Messenger (ﷺ) said, 'I have been ordered (by Allâh) to fight the people till they say: La ilâha ill-Allah (none has the right to be worshipped but Allâh) and whoever said it then he will save his life and property from me except on trespassing the law (rights and conditions for which he will be punished justly), and his accounts will be with Allâh." Abu Bakr said, "By Allâh ! I will fight those who differentiate between the Salât (prayer) and the Zakât, as Zakat is the compulsory right to be taken from the property (according to Allâh's Orders). By Allâh ! If they refuse to pay me even a she-kid which they used to pay at the time of Allâh's Messenger (ﷺ) I would fight with them for withholding it ". Then 'Umar said, By Allâh, it was nothing, but Allâh opened Bakr's chest towards the decision (to fight) and I came to know that his decision was right." [2:483-O.B.]