Source of Milton's idea that God tilted the Earth's axis after the fall of man

Question

Could someone please help me identify the source of the following passage in Book X of Paradise Lost:

Some say, he bid his angels turn askance
The poles of Earth twice ten degrees or more
From the sun's axle; they with labour push'd
Oblique the centric globe: some say, the Sun
Was bid turn reins from th' equinoctial road...

To clarify: in all editions of PL available to me, I have found only general comments about geocentrism and heliocentrism. I am looking for a specific source of the idea that God tilted the Earth's axis as a way of punishment. It makes sense to suspect that Milton had a particular source in mind, to which the phrase 'some say' alludes. Would really appreciate any help with identifying those 'some'.

Answer 1

The notion is that in the Garden of Eden, the original pre-Lapsarian world, there were no seasons but an eternal springtime. Then at a later date, God introduced the seasons as part of a general decline, which in the Bible is attributed to God's punishment of man for the sins of Adam and Eve in the Garden.

This is an old idea that goes back to Classical Rome. It's in Ovid's account of the four ages of man, in Metamorphoses book One (see Wikipedia). Ovid writes of the Golden Age

Western winds immortal spring maintain'd.

Then comes the Silver Age:

Then summer, autumn, winter did appear:

And spring was but a season of the year.

The idea of the different ages of man was a commonplace of classical Roman thought, but Ovid seems to have given it a particularly clear expression in a work that was widely read in the early modern west.

Renaissance thinkers linked this with the Biblical narrative of the fall of man, although Roman Christians may have made a similar connection long before (see Milton and the "Seasons' Difference", S. Viswanathan, Studies in English Literature, 1500-1900, Vol. 13, No. 1, The English Renaissance (Winter, 1973), pp. 127-133 on JSTOR).

Knowledge of the tilt of the earth's axis was known even before Classical Rome, to the ancient Egyptians and Chinese around 1100 BCE. Pytheas measured it in 350 BCE to a greater accuracy than what Milton cites.

It was known that the tilt of the axis was connected with the seasons (together with the different length of days and the height of the sun at noon). No tilt means no seasons. So Milton put all this together to link the tilting of the earth's axis with the Fall of Man.

Answer 2

The Oxford World's Classics edition (2004), with notes by Stephen Orgel and Jonathan Goldberg, explains it as a necessary shift from the "prelapsarian eternal spring" to the course of seasons and the course of the sun between the tropics of Cancer and Capricorn as we know it: "To account for the prelapsarian 'eternal spring', Milton assumes that before the fall the sun's course coincided with the celestial equator." (p. 260)