Revelation of the Daleks is a rather morbid episode set at a galactic funeral home. It has much comedy in it, as always, but some of the humor is blacker. The Doctor and Peri arrive on the suitably-named planet Necros, supposedly for the funeral or memorial service for a friend of the Doctor’s. The Doctor (we later learn) already suspects that something is not right, since his friend, Professor Arthur Stengos, is not the sort of person to go for an elaborate ceremony.
The initial discussion of wearing appropriate attire for a particular culture (in this case the “traditional blue or mourning” and, for females, covering their legs) can provide a starting point for interesting discussion of cultures and their customs, and the appropriate way of adapting to a culture not one’s own.
The episode could perhaps be summed up in the phrase “Soylent Green is those people fortunate enough not to be made into Daleks.” The planet Necros is also the center for distribution of a protein food product to planets which otherwise would face starvation. And as we learn by the end of the episode, the food is made from the people who are supposed to be cryogenically stored at the facility.
The luckier ones, that is, and the remains of the rest.
Because also present on the planet is Davros, working to create a new breed of Daleks, experimenting with ways of turning humans into Daleks.
Davros is going by the name “the Great Healer.”
In the end, Davros and his Daleks are defeated by Daleks from Skaro who answer to the Supreme Dalek, and view Davros and his newer Daleks as rebels. Davros is to be taken to Skaro to stand trial.
Oh, and I have to mention that Davros in this episode can apparently shoot Sith lightning!
As far as religion is concerned, Tranquil Repose (the funeral parlor/cryogenic suspension center where most of the action takes place) is filled with religious iconography from a range of human religious traditions, including Catholicism and Hinduism. There is at least one Biblical allusion: to every paradise having a snake. And there is more that is related to religion on a more subtle level, such as Davros being said to have disciples, like all fanatics, and Davros promising someone immortality (as a Dalek) in exchange for serving him with their total being. Also noteworthy is that the Doctor, in the face of his own mortality, does not seem to turn towards anything we might call spirituality for comfort.
Let me close by mentioning that, regarding the name “Tranquil Repose,” the Doctor quips that it is evidence that America doesn’t have the monopoly on bad taste.”