What's a corrupt nature? How can you know that one's being is corrupt versus uncorrupt? Who is this Jesus fellow you say wasn't in possession of a corrupt nature? Is there anything outside of your one text corroborating any of this?
A corrupt nature is basically one that is not operating as God created it to operate. Before I answer any more, keep in mind that these questions are asked in light of the Bible. These questions aren't about actual evidence and me presenting my case in that fashion. I'll have that discussion later on hehe! Yet in terms of the biblical terms, man was originally made in the image of God. So in essence, our nature mirrored His. How can we tell a corrupt nature? By trying to keep the Torah or Law. Now, Jesus made it even clearer for us when it comes to the commandments, that even if you dwelled on things counter to the law, you are breaking it. That if you lust after someone, you commit adultery. If you hate someone, you a muderer and break those commandments. So the Law reveals our true nature, because of course we want to lust after good looking people right? It's just not how God created us. Now the text say Jesus wasn't born with this nature, but was born after God's nature. (Like the first Adam) I can't comment what's outside the text and what governs what outside it, but this discussion is concerning the text.
Pick any. Perhaps the parable of the good samaritan
Well, teachings like that I agree aren't dependant on a literal Genesis. Anyone can do good things and things like that. Yet what's dependant on a literal Genesis is the whole reason why God is at odds with the world. If God created the world like we see it today, or that we came about through the accepted history of the world, that eliminates the need for Jesus to come and "save" us. Save us from what exactly and redeem us from what exactly, if there wasn't a fall of creation in the beginning? So I argue, the whole set up for Jesus coming to redeem us, hangs on a literal Genesis.