I believe in the communion of saints, and one of the big things that means for me is reading. Via my bookcases, I can enjoy the theological insights and Christian experiences of believers who have gone before me. The brains of people from every continent and every century of the church are available to me. (My own bookcases may not actually sport books from every century; I am still collecting!) But reading dead theologians can be tricky. Here are a few tips:
1. If approaching a new dead theologian - that is to say, one you've not read before - try to find out whether they've written something devotional, or at least practical, and read that first. It's helpful to have a feel for what makes someone tick in terms of their own spirituality before hitting the doctrine.
2. Do remember that dead theologians are often working in very different intellectual and cultural contexts. This has lots of effects that need to be borne in mind. At the nuts and bolts level, there may be technical vocabulary that translates awkwardly (or, if they were writing in English, there may be vocabulary which wasn't technical then but is now, or which was technical but which the writer could assume an understanding of which is no longer current...) But above and beyond that, there is the philosophical outlook employed, or assumed, or perhaps even being opposed.
3. As a corollary, don't be too quick to assume you know what the dead theologian means. Sometimes the words and concepts seem familiar, but the different philosophical climate changes the meaning completely. Sometimes we import too much from our end of the conversation and assume that the dead theologian must be addressing an issue which we face - an issue which may never have even occurred to them. Best to read slowly and without jumping to conclusions.
4. Don't assume that because the dead theologian was right to say such-and-such
then, that we ought to say the same now. There may be specific reasons why they expressed themselves in that particular way, and it may have been not only necessary but also best to say exactly that in exactly that way. But perhaps outside of that particular controversy,or when working within a completely different philosophical paradigm, or in a different ecclesiastical context, it would be better to say it differently, or leave it un-said.
5. Vice versa, don't assume that just because you wouldn't say such-and-such
now, that the dead theologian was wrong to say it then. Don't judge those of past ages by our present orthodoxies, or at least don't be too quick to do so.
6. Don't assume the dead theologian got the question right (or that the question as posed is still relevant). Sometimes theologians end up with particular answers because they asked particular questions (or particular questions were put to them) - and those may not be the best questions. They could have been imported from a non-theological framework, or they could have been raised due to a misunderstanding. The answers may be very fine, but we should not therefore assume they are theological truth unless we have also examined the questions.
And the two big ones...
7. Don't treat the dead theologian as if they are dead. In Christ, all these people live, and as living people they still speak through their works. That means we have to pay attention, as in a conversation, not just use their relics as a springboard for our own thinking.
8. Do remember that the dead theologian, if he or she was really a theologian, was looking to Christ. The best thing we can do with their works - the thing they would want us to do with them - is to use them as windows through which we can glimpse him. And that is the value of reading them. Because they are far removed from us, their perspective is different, and they will see Christ in ways in which we would never see him left to ourselves.
And it is worth remembering that one day we, with them, will see him - and then all our theological differences will be as nothing.