Question: "Whence comes despondency? And what should one do when it appears?"
Response: There is a natural despondency that comes from weakness, and there is a despondency that comes from a demon. If you want to test these, do so in the following way. Despondency that comes from the demon appears just before the moment when one requires rest. For when one begins a task, even before completing a third or a quarter of the work, despondency drives one to abandon the task and leave. Therefore, one should not tolerate it, instead praying, remaining seated for the task, and persisting. For when the enemy sees that one is praying for this reason, he ceases; for he does not want to give any opportunity for prayer. Natural despondency arises when one labors beyond one's strength and is obliged to refrain from doing any more. Therefore, natural despondency is caused by bodily weakness. In this case, one should test one's strength and give rest to the body in godly fear.
+Sts. Barsanuphius and John, from Letters, Volume 2, #562
