More Dean/Michael and Sam/Lucifer parallels:
In the early seasons (which are really the only seasons I use for this parallel, thanks writers), Dean and Sam both show a startling lack of morals in regards to interacting with other people, but in different ways. Dean doesn’t seem to mind physically hurting people he thinks deserve it, nor does he mind telling impersonal and/or white lies. However, he goes out of his way not to fuck with people’s heads and he’s brutally honest when he needs to be.
Sam, on the other hand, doesn’t like the idea of being the one to inflict physical harm (though he does seem to enjoy doing it once he’s started, which is a topic for another post), and he doesn’t like telling “official” lies. He doesn’t mind manipulating people or telling personal lies, though, and he will spare people’s feelings at the expense of the truth.
Later, in s5-6, Lucifer shows that he generally prefers not to get his hands dirty until the violence will have some personally satisfying aspect. He also is a master manipulator and lies left and right. Michael, on the other hand, doesn’t outwardly derive any enjoyment from violence, but doles it out much more readily and efficiently than Lucifer. He also has trouble lying, and, in TSRTS, goes out of his way to explain his reasoning to Dean and make sure he knows everything.