The plain fact is that Jesus taught no theology whatever. […] Historical Christianity, unfortunately, has largely concerned itself with theological and doctrinal questions which, strange to say, have no part whatever in the Gospel teaching.
(Sermon on the Mount, Emmet Fox, introduction)
Fox then goes on to list theories concerning original sin, vicarious blood atonement, infinite punishment for finite transgressions, and predestination as examples of these add-ons.
It is probably important for anyone exploring Christianity to distinguish between what is core in Christianity, and what is secondary or derivative. Much of what is criticized, and what causes intellectual problems, is not the core of the Gospel message (say) – in a nutshell, peace, hope, and love – but rather derivative theological reasoning.
Once you realize that human reasoning is easily misled, it is a short step to demoting much of theology to a tentative status. Something to be held conditionally, as perhaps a ‘best current attempt’ or heuristic. If what is (actually) a speculative line of reasoning is conflicting with one’s common sense, say, the appropriate answer is usually to say ‘So much the worse for the theology!’