The following example is adapted from another ELL post
in short, the period was so far like the present period, that some of its noisiest authorities insisted that it be received
where a "that clause" is used,
insist that. The question is the part immediately after that, namely, "it be received".
To me, it is easier to understand if that could have stated
... some of its noisiest authorities insisted that it should/could/would be received
On the other hand, I found lots of people using the expression. Therefor, that would be a commonly used expression that I don't understand.
So, what does "that it be" mean?