Most probable answer: the Holy Spirit moved John.
I get that exact comment every time I post one of these videos.
I understand where you’re coming from as far as all scripture being of inspiration from the Spirit. But what I don’t understand is why that automatically seems to disqualify the historical reasons the books were written in people’s minds. It can’t have a God-inspired AND historical meaning?
For example, it’s nice to think that the Spirit just moved on John and told him to write things. But III John is specifically addressed to Gaius, delivered by Demetrius, warning to avoid the sins of Diotrephes. Aren’t you in the least bit curious of knowing who these men were, and what was urgent enough to move John to give such a dire warning? And is there something we today can learn from it?