What is the required manner for a leader (Amir) to travel with his army?

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The Amir must travel at the pace of his weakest soldiers so as not to overburden them. However, if there is a compelling need to accelerate the march, it is permissible. Evidence for acceleration is found in the precedent where the Prophet (peace be upon him) proceeded with extreme haste upon hearing the words of Abdullah ibn Ubay, intending to occupy the people with the march rather than the slander. Furthermore, Ibn Umar hastened his travel when summoned regarding his wife Safiyyah.