US pastor Eugene Peterson, 85, was admitted to hospital last Tuesday and is currently being treated for pneumonia.
His son Eric shared the news in an email to Robert Creech, a professor of Christian ministries at Baylor University's Truett Seminary, giving him permission to share the letter online.
In the post shared on Facebook, Creech said of the Presbyterian preacher: "He has refreshed scripture for many through his thoughtful paraphrase of the Bible published as The Message.
"He has taught us to pray. It is time for those who have benefited from his ministry to return the favour to him and his family with prayer over the next several weeks as Eugene has been placed in hospice care."
The letter says: "He is now being treated for pneumonia and is responding well to the IV antibiotics. He is eating again, and went for a very short walk this afternoon. He is much improved as of today."
However, the pastor's health care team of three doctors informed the family that "he will come under the care of hospice and his medical care will be primarily palliative".
The letter by Eric goes on to say: "When I summarised the conversation with him later, I told him there were three main things for him to know. One, you are deeply loved.
"Two, it appears that you are in the last months of your life. And when I asked him how he felt about that, after some thought, he said, 'I feel good about that'.
"Three, we are going to try to help make these remaining months as comfortable and enjoyable for you as possible. To which he gave us his million dollar smile and said, 'thank you'."
Messages of prayers and thanks for the pastor and his family have been shared online.
Jason Edwards commented on the Facebook post: "I wrote him a letter several months ago and his son was kind enough to write me back about his dementia.
"I've been grieving for him and them since then. This is sad news. I don't know him, but I love him."
Donna Woods Barron posted: "Robert, thank you for sharing your loving tribute to such a remarkable man. I shall pray for his peace in these last days."
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