Welcome! Please don't take the downvotes as a sign that you aren't welcome here. (They probably do indicate that things that look like proselytizing won't be well received, though.)

I think translating "λόγος" as "rationality" is a bit of a stretch. I don't know of any English translations that even render it as "reason", which is more defensible. I expect you're right that the authors of the New Testament didn't see any conflict between their beliefs and reason; people usually don't, whether such conflict exists or not; in any case, our epistemic situation isn't the same as theirs and it's possible that in the intervening ~2k years we've learned and/or forgotten things that make the most reasonable conclusion for us different from the most reasonable conclusion for them. (Examples of the sort of thing I mean: 1. The success of science over the last few centuries means that the proposition "everything that happens has a natural explanation" is more plausible for us than for them. 2. The author of John's gospel, or his sources, may have actually met Jesus, and perhaps something about doing so was informative and convincing in a way that merely reading about him isn't. 3. We know the history of Christianity since their time, which might make it more credible -- after all, it survived 2k years and became the world's dominant religion, which has to count for something -- or less credible -- after all, people have done no end of terrible things in its name, which makes it less likely that a benevolent god is looking on it with special approval. 4. We have different examples available to us of other religious movements and how they've developed; e.g., we might compare the early days of Christianity with those of something like Mormonism, and they might compare it with the Essenes.)