I think you're on to something. Without language, of course, even basic communication from one to another is impossible. But the only thing standing in the way of pure understanding is language.
words are great.
Your circular attempt at reason is another thing all together.
This is as much to say as Truth is necessarily subjective, that is "felt". Objective and Subjective are modes of knowing, and the preminence of science has elevated the former over the latter, but the Greek sophists argued that the subjective is primary, and the objective secondary, that is constructed ... communicated ... external. Our entire personal reality is in fact subjective.
I don't see it quite that way. Standing in the way - yes, there are schools of thought that feel that the intellect is a hinderance or worse to knowing the ultimate truth (or truths - depending on your belief) - I don't think so myself.
Pure understanding - what is it? I think really that is knowing or experiencing... which comes back to that being an non-intellectual, therefore non-language - experience.