Been catching up on Dracula Daily and wow. There is a whole lot of Christian biblical imagery going on, especially references to the Gospels.
To build on that, it’s especially obvious with Mina’s “unclean” speeches. There’s a few things going on with “uncleanness” (at least in the KJV, anyways). There’s ritual uncleanness* (e.g. eating certain animals, handling corpses, etc), as well as references to character faults or sins (this type of reference to uncleanness is primarily in the epistles and is much less common in the Gospels; it tends to deal with things like lust or greed). (There’s also a fair few references to unclean things in Revelation, but I’m not gonna get into that).
The most common reference to anything “unclean” in the Gospels** are verses that use “unclean” to specifically reference possession, e.g. “an unclean spirit.” This can be seen in Matthew 10:1, Matthew 12:43, Mark 1:23, 26-27, Mark 3:11, Mark 5:2, 8, & 13, Mark 6:7, Mark 7:25, Luke 4:33 & 36, Luke 6:18, Luke 8:29, Luke 9:52, and Luke 11:24, all of which involve the casting out of “unclean” possessing spirits.
That Mina is calling herself unclean before being burned by the Host (and presumably “purified” by it) is almost certainly a biblical allusion, especially given the Count’s hypnotic and possessive abilities. In addition to possession scriptures, leprosy also comes up many times in the Gospels, and in this context lepers are healed and thus allowed to rejoin the community. The Count is usually written as an inversion of Jesus, and that’s what seems to be going on with Mina (instead of his touch purifying, it corrupts; instead of being able to rejoin the community, she needs to isolate herself because she is unclean).
*Without having an authoritative source to point to, I recognize that scriptures like Matthew 23 that chastise Jewish leaders for religious observance are antisemitic and have almost certainly been used to justify antisemitic abuse. I bring that up because the imagery used in that chapter in particular, especially about ‘whited sepulchres’ which ‘appear beautiful outward, but are within full of dead men’s bones, and all uncleanness’ with reference to Jewish leaders are unfortunately relevant to recent Dracula chapters and the count’s description, and whether or not the in-book description of Dracula was directly intended to be antisemitic abuse, or just straightforward horror/death imagery referenced during a wider antisemitic cultural zeitgeist, I think it’s definitely part of the general antisemitic nature of a lot of vampire literature. I don’t have the historical knowledge to say more than that or make commentary, but I didn’t want to ignore it.
**Unclean spirits are also referenced in Acts prior to Peter’s vision about eating animals, as seen in Acts 5:16, Acts 8:7. I don’t know enough about the historical context to speak more eloquently on the historical ramifications of this and recognize that this has almost certainly been used as a tool for antisemitism, so I’m gonna stop here but did want to bring it up.