Well, most straight-up death metal is going to contain things like that... Nile Dim-Mak, and Decapitated come to mind as "clean" death metal bands, with my personal favorite being the latter. For not so clean... Origin, Cryptopsy, Vehemence, Bloodbath...
Then, you have your technical death [ie: Death, Cynic, Atheist, Theory In Practice, The Red Chord, Gorguts]. which is generally concerned with metaphysical things. Now, what's tech and what's not, according to this thread, is debatable. Those are just the few DM bands I like, and where I consider them to be.