Sayyiduna Muhammad bin Abi Amirah (may Allah be pleased with him), who was one of the Companions of the Prophet (peace and blessings be upon him), said: "If a servant were dragged on his face in obedience to Allah from the day he was born until the day he dies of old age, he would still regard it as insignificant on the Day of Resurrection, and he would wish that it had been increased for him, just as reward and recompense are increased."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16611