Since no one really knows what was in the minds of the people who wrote the Bible, it is difficult, if not impossible, to interpret. We can only make guesses. Different translations, and changes in the meanings of words over the centuries have added to the confusion.
The Prophets and Apostles all had inner circles of intimate acquaintances. These heard their sentiments in general. When they delivered a Message for them to others, they had general Knowledge of the Writers' Teachings, out of Which to amply amplify the Written Content.
I rarely. if ever, fail to perfectly interpret the meaning of even the most oddly worded notes written by those I know best. If my brother had a recorded speach, famous to all, I could fill in much of the releted thought for others that never got to ask him what he thought behind his words. Others, then, that took note of my interpretations could pass them on alongside the speach as a tradition both written and oral, and very articulate, worthy of authoritative appeal for all generations.