On a secular message board I visit there is an ongoing discussion of if there is a hell and if there is do you believe you will go there. (if you're interested you can find that discussion here
In that thread, there are many arguments and counterarguments about various points of Christian, and Muslim teaching. It reminded me of another thread on that board on the divinity of Christ where I quoted sections of St. Athanasios' On the Incarnation
and posted a link to the entire work on the St. Pachomius website, which worked well with this very secular group of people. I am wondering what other patristic sources are very good to use in discussions with nonbelievers and people of other religions?
Here are a few I am personally familiar with:On the Divine Images
by St. John of Damascus. A WONDERFUL treatise of why icons are necessary in an incarnational faith. The source of the famous quote "In former times God, who is without form or body, could never be depicted. But now when God is seen in the flesh conversing with humans, I make an image of the God whom I see. I do not worship matter: I worship the Creator of matter who became matter for my sake, who willed to take his abode in matter: who worked out my salvation through matter. Never will I cease honouring the matter which wrought my salvation! I honour it but not as God." On the Incarnation
by St. Athanasious the Great. THE culmination of the teachings of St. Athanasious, who defended the teachings of the Church against Arius at the First Ecumenical Council. The SVS Press version also includes the wonderful introduction by C.S. Lewis. If you have another printing of this work, the introduction can be found here
What I am really interested in is a book similar to the above on the Holy Trinity. The only one I am familiar with is Augustine's book on the Trinity that pretty much set up the West for many of the unorthodox teachings they have today.
Please list your suggestions and why you suggest the work. Perhaps this may become part of Orthodox Answers...