Some further responses by Lydia:
I'm also completely unmoved by the repeated idea that I see in various places that Jesus is enjoining only against saving oneself by some public act of denial, not against trying to save others. This idea that it's wrong publicly to abjure one's commitment to Jesus only if one does it for self-centered motives but not wrong if one does it "nobly" to save others is entirely anachronistic and foreign to Scripture. Scripture not only does not recognize such a distinction, it positively rejects it.
Presumably, Lydia doesn't think it's entirely anachronistic and foreign to Scripture in general to protect the innocent from harm. Does Lydia mean there's no one verse of Scripture that contains that distinction? In systematic theology, we attempt to integrate various Biblical teachings. How what Scripture says in one place relates to what Scripture says in another place. Many distinctions are drawn by theological synthesis.
When Jesus says to "hate" your parents and children in comparison to your commitment to him, he adds at the end, "And your own life also." In other words, it's not as though you're being told just to hate your own life but to do whatever it takes to preserve the lives of the others.
Except that I already noted that Lydia rips that passage out of context. So she's not engaging the counterargument. She's converted that passage into a universal, unconditional command–in defiance to the context.
Similarly, when the man tells Jesus he wants to follow him but first must go and bury his father, Jesus rebukes him. He does not say, "Okay, I understand that you want to delay following me for an unselfish motive of honoring your father, so that's okay. It's only if you hold back on following me for the sake of your own self that there is a problem."
i) It begs the question to say the priest (in Silence) is not following Jesus if he commits public sacrilege to save others from torture and/or murder. Whether or not that's consistent with following Jesus is the very point at issue.
ii) Likewise, the question at issue is not whether we have a higher allegiance to Jesus than we have to family, friends, neighbors, strangers, and enemies. Rather, the question (or at least one question) is whether this is, in fact, a case where it would be substantively disloyal to Jesus to commit a symbolic act of sacrilege to spare the innocent.
Put another way, does Jesus require Christians to sacrifice the innocent? Does Jesus make that a litmus test of fidelity to himself?
iii) By the same token, the case of the son who says he can't accompany Jesus until he buries his father isn't obviously analogous to a priest who steps on an icon of Jesus to save the innocent from torture or murder.
I find it understandable emotionally that one would try to invent such an exception in Jesus' injunction, but I find it entirely indefensible rationally.
i) Are we "inventing" an exception? For instance, there are well-meaning Christians who treat Proverbs as a promise box. Then they become disillusioned when God "breaks his promise". But they overlook the fact that Scripture often states maxims and general principles which are understood to admit exceptions or qualifications depending on the circumstances. These are guidelines, not predictions or promises.
ii) In addition, the teaching technique of Jesus includes abundant hyperbole. Does Lydia think sanctification requires amputation (Mt 5:27-30)? Gouge out your eyes and cut off your hands? Given the hyperbolic nature of so much dominical teaching, it's not "inventing exceptions" to make allowance for the possibility that a general statement may be an overstatement for emphasis.
Jesus' injunction is about the incredible badness of denying him before men! Jesus isn't making a point about the badness-with-an-insufficiently-noble-motive.
Jesus routinely upbraids the religious establishment for failing to take motives and intentions into account when they interpret and apply the law. He upbraids the religious establishment for failing to consider the rationale for a particular injunction. What's the purpose of that injunction? Is that injunction a means to an end or an end in itself?
If saying, "I renounce Jesus," etc., isn't an intrinsically wrong act, I really don't know what is, given what Jesus says and given the very nature of Christianity, as argued in the post. And if it's intrinsically wrong, then it doesn't matter whom you are trying to save by doing so, just as in any of the other millions of consequentialist scenarios that one gets confronted with. There is no way to make Christianity safe for consequentialism. There just isn't.
This is one of Lydia's intellectual shortcuts. She always likes to cast the issue in terms of consequentialism v. deontology. But I didn't rely on consequentialist principles in my assessment of her position.