[The need for sagacity in fighting against Muslims :] O creatures of Allāh! I advise you to have fear of Allāh because it is the best advice to be mutually given by persons, and the best of all things before Allāh. The door of war has been opened between you and the other Muslims. And this banner will be borne only by him who is a man of sight, of endurance and of knowledge of the position of rightfulness. Therefore, you should go ahead with what you are ordered and desist from what you are refrained. Do not make haste in any matter till you have clarified it. For in the case of every matter which you dislike we have a right to change it.