Gods and divine beings in Japanese fiction typically speak in two flavours of diction: 1) Archaic sounding language (with a dash of modern words here and there) and 2) Modern language, whereof the second category there is a subset where the gods speak purely in polite language almost never relenting on this unflinching courteousness.
No matter to whom they are talking, mortal or immortal. Higher or lower in the cosmic hierarchy.
One example shall suffice for this analysis: Princess Kaguya from Tecmo Koei's Warriors Orochi series.
Why is it that gods even need to be speaking in polite language?
Let us take a look.
Kaguya-hime:
なんと鮮やかな戦ぶり……。時の許す限り、拝見いたしたく存じます Nanto asayakana ikusa buri... Toki no yurusu kagiri, haiken itashitaku zonjimasu "Such deft war-arts.... I shall like to most humbly witness this along as time itself permits me."
Haiken ("to humbly behold"), itasu ("to humbly do") and zonjiru ("to humbly know"), all of these three make up "shall like to witness" and as such also represents the most extreme that the kenjougo ("humble speech") has to offer. And a perfect introduction!
She could as well have said, for the last part,
見たくて思います Mitakuteomoimasu "(...) I want to see"
Using the reguer miru ("to see") and omou ("to think"), albeit in their polite forms and convey a neutral sense of politeness.
She is based off a lunar princess of the Japanese fairy-tale, The Tale of the Wood Cutter, telling the story of how a poor wood-cutter finds within the innermost part of a bamboo shoot a young child that quickly grows to become a radiantly beautiful princess, hence the name kaguya which anciently meant a "bright night."
Now, Kaguya is, granted, an exception since she also uses archaic elements such as the negation nu. Her personal pronouns watakushi and anata-sama are nonetheless marks of the most reverential language possible within Japanese, though the formality is rarely seen.
Her status as stellar and ancient nobility prompts her to speak in such a old fashioned manner of politesse.
She, even when admonishing other gods or mortals for their immoral conduct keeps her courteous tone:
(...)