Jabir told that God’s Messenger used to keep to the rear when traveling and urge on the weak. He would take someone up behind him and would make supplication for them all. Abu Dawud transmitted it.
Hadith Referenceمشكوة المصابيح / كتاب الجهاد / 3913
Hadith Gradingالألبانی:جيد | زبیر علی زئی:صحيح
Hadith Takhrij´تحقيق و تخريج: محدث العصر حافظ زبير على زئي رحمه الله` «صحيح، رواه أبو داود (2639)»