According to Christian teachings of the day, God ​controlled the heavens, rendering them unknowable to our feeble mortal minds.

What’s “teachings of the day”? I know what “teachings” means, but does “the day” mean literally “a period of 24 hours”?

Thank you for your help!

See a translation

@HuLuoNan "Of the day" means the during whichever time period you're talking about. It does not mean a 24-hour period.

Of the day = time period or era

So if you're reading about Christianity during the second century then the second century would be "of the day". (Meaning during that time period.)

If you're reading about Christianity in the 15th century then the 15th century would be "of the day".

If you're reading about Christianity at the turn of the 20th century (1900's) then that would be "of the day".

If you're reading about Christianity on the 1950's then that would be "of the day".

Example: I like fashions from the 1950's. The styles of the day were very structured and fitted.

Let me know if that makes sense or not.