I've heard the idea that Kayin was the one who inspired his brother Hevel to bring an offering to Hashem (Genesis Chapter 4). One possible place I saw this was from Rabbi David Fohrman, although I don't remember if I heard it elsewhere. Either way, the verses aren't explicit, just that Kayin brought something, and then Hevel.
I'm wondering if there are any classical sources which discuss the fact that Hevel was inspired by Kayin's idea to bring an offering. Bonus points if the source discusses why this wasn't a merit or zechus for Kayin. We find that Yehudah had a zechus because he inspired Reuven to repent (see Rashi to Deuteronomy 33:7), and I'm wondering why Kayin was different. Or if there was a zechus, how did it manifest?