Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: On the day of Badr we were two or three riders to a camel, and the two companions of the Prophet (peace and blessings be upon him) were Sayyiduna Ali and Sayyiduna Abu Lubabah al-Ansari (may Allah be pleased with them both). When it was the turn of the two of them, they would both say: O Messenger of Allah, ride, and we will walk. He (peace and blessings be upon him) would say: "You two are not stronger at walking than I am, nor am I indifferent to the reward."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10357