This is an interesting section:
“The cures for the spirit also have been discovered by the ancients; but it is our task to learn the method and the time of treatment. 9 Our predecessors have worked much improvement, but have not worked out the problem. They deserve respect, however, and should be worshipped with a divine ritual. Why should I not keep statues of great men to kindle my enthusiasm, and celebrate their birthdays? Why should I not continually greet them with respect and honour? The reverence which I owe to my own teachers I owe in like measure to those teachers of the human race, the source from which the beginnings of such great blessings have flowed.”
It’s not always clear to me when you are engaging in figurative language versus telling us what you actually do. I suspect, however, that here at least, you mean what you say and say what you mean.
I also suspect that the apotheosis of teachers which is intimated here would be distasteful to many these days. The god-like nature of Sages seem well established, if only because most folks believe it to be an unattainable state.
Did Zeno and the folks of the early Stoa believe themselves to be Sages? I think that answer is yes, despite the middle and late Stoa’s stepping away from that title.
It seems, though, that you, Seneca, are harkening back to that early Stoic doctrine of the pseudo-apotheosis of the Sage in treating your teachers in this way.