Angel of Death has matter of fact lyrics. There is no moralizing. Slayer do not have to moralize like a stupid Hollywood movie to tell you that guys like Mengele, Dirlewanger, and Shiro Ishii were awful human beings who deserved to die. If upon hearing what they did, someone doesn’t think that they deserve to die or wants to waste resources feeding and housing them apart from society while children starve on the street, then there is something wrong with them. The most human and metal response is to just want to kill them. Slayer evoke that. Spiritually? Metal lyrics are mostly about Satan, serial killers, and burning the church. Literally.