Identify this story about the end times from the Desert Fathers I heard a story similar to the following at some point, but for the life of me I can't find an authoritative source. I believe that it's one of the Desert Fathers, but I'm not certain of that, either. Here it is, paraphrased from memory:


  A novice asked to the father whether the fathers of ancient days were greater than the ones of today. And the father said, "Those who came before us did greater works than us, and those who follow us will be weaker still. And in the last days men will not be able to do any kind of spiritual labor at all, but those who endure to the end will be saved."


Any help?
The story appears in the alphabetical collection of The Sayings of the Desert Fathers, translated by Benedicta Ward.  It relates to a saying of the 3rd century Egyptian monk (and martyr), Ischyrion.


  The Holy Fathers were making predictions about the last generation.  They said, "What have we ourselves done?"  One of them, the great Abba Ischyrion replied, "We ourselves have fulfilled the commandments of God."  The others replied, "And those who come after us, what will they do?"  He said, "They will struggle to achieve half our works."  They said, "And those who come after them, what will happen?"  He said, "The men of that generation will not accomplish any works at all and temptation will come upon them; and those who will be approved in that day will be greater than either us or our fathers."