Paul and his missionaries probably had Post Traumatic Stress Syndrome.

It was a suffering that the apostle said was like a death sentence. Second Corinthians 1:9 states, “indeed we had the sentence of death within ourselves.” The Greek word for “had” carries the idea of still having a vivid recollection of that experience. In today’s language, we could say that the missionaries had PTSD. The great lesson here, for our purposes, is that when a person is biologically or spiritually depressed to this point, they can look to God and know. that not only this type of suffering, but also the deliverance that will come is from a merciful, and loving Father. God is a great deliverer of His suffering people. 

Paul goes on to talk about God’s deliverance from sorrow, grief .and depression, he “who delivered us from so great a peril of death, and will deliver us, He on whom we have set our hope, and He will yet deliver us” (2 Cor. 1:10–11). It all became part of the Holy Writ. It has been tested throughout history that the compassionate, merciful Father has a way of delivering his people. 

Paul said that he had learned that the Lord, who had delivered them in the past, was delivering them in the present, and would deliver them in the future.
 The following quote from Lange’s commentary is helpful on this passage. Of all persons in the world, the minister of Christ should know what true consolation and a cheerful spirit is. Only those who have comfort can impart it






"A theologus non tetanus, a minister without an experience of personal trials in religion, lacks an important qualification for his work. The more afflictions, the more power he has; and the moment he enters the furnace of affliction, he has a virtual announcement from the Lord that some great work is before him, and that God is preparing him for higher usefulness. The soldier who is allowed to remain continually around the camp-fire will never learn true bravery. A minister’s afflictions deepen the impression of his discourses. The admonitions of a veteran general have a power which no young captain can ever have 
Langes' Commentary of  Second Corinthians, public domain).This quote comes from Steve Bloem's new book. The Pastoral Handbook of Mental Illness: A Guide for Training and Review.ppl 12, 13. How can you buy It?  https://www.amazon.com/Pastoral-Handbook-Mental-Illness-Reference/dp/0825444667