Generative Question

In the simile in line 591, why does the sentence begin with "his" and then change genders to "her"? Are they two different things, is Milton referring to mother nature?

The responses i recieved stated that the "he" is the devil and the "she" is referring to mother nature. Then the response compared satan to a giant and related that to when Satan comes out of the water, he decieves everyone, thinking that he is a huge rock, and then turns out to be this huge giant. Then the response i recieved said "Even though he has become evil", but one question i have is was satan evil before or after god sent him to hell? Because maybe he didn't become evil, maybe he already was. That response i did not agree with, although there were some solid points on how nobody can be purely good or evil, everyone has a little bit of both inside them. So the whole theory of heaven and hell is pointless, because sometimes people do good things, and then at times they can be malicious, but does that mean they need to get sent to this hopeless place? Also it relates to what is bad and what is good, for example In my eyes i feel that stealing is sinful, but what if that person stole food to feed his children? There are different ways of percieving good and evil, and it is unfair for Satan that god is treating him in this way.