It is narrated from Sayyiduna Utbah bin Ghazwan (may Allah be pleased with him) - who was the brother of Banu Mazin bin Sa'sa'ah and was one of the Companions - that the Prophet of Allah (peace and blessings be upon him) said: "Indeed, after you will come days of patience; whoever at that time holds fast to the like of what you are upon will have the reward of fifty of you." They said: O Prophet of Allah! Fifty of them (those who come later)? He (peace and blessings be upon him) said: "No, rather of you." They said again: O Prophet of Allah! Of them? He (peace and blessings be upon him) said: "No, rather of you." He said this three or four times.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14361