My apologies, Nick. I saw your question the other day, and I meant to get back to if before now, but have been unable to come up with the time it deserves, for it's a good question.
You've basically grasped it, I think. At least, you've grasped one key aspect of the argument presented in the OP. Let me state that as a principle, please. If you call upon people to take action, then it is logically permissible in certain specific circumstances for the meaning of your words to be defined in terms of the actions they take. The 'specific circumstances' are mostly that you know your audience well enough it's reasonable to suppose you are tailoring your words to them so that they will be less likely to misunderstand your meaning.
In my opinion, that principle doesn't look like much unless you're willing to carefully think about it. It's one of those things that can be hard to see unless some reasonable effort is made to see it. However, there are presumably lawyers who would quickly recognize it as a principle of American law in at least some circumstances.
Here's an interesting contemporary application. It is almost certain, I've heard, that the principle will soon be brought up as relevant and necessary to making a case to convict Trump in his Senate trial. The challenge is that in order to convict him of the charges against him, it must be shown that Trump's words on or before 1/6 can be legally (and logically) construed as instructing the terrorists to do what they ended up doing and demonstrably intended to do at the Capitol Building.
To put that concretely, take for one example when he tweeted prior to 1/6 that his followers should show up in Washington that day, and then famously added, "It'll be wild", how can we determine what those words meant in that context to those of his followers who heard them? Arguably, it's reasonable to think that, when it can first be established who someone is talking to, it can be assumed that's who they are trying to communicate with. Which means, that's who they are shaping their words to convey meaning to.
Now, that right there is a blow to the "His words could have meant anything to anyone" nonsense. The principle means the exact opposite of that. That principle points a means whereby the meaning of a person's words can, under certain circumstances, be decided to an exacting and precise degree.
To take it a step further, now, if we accept that it is reasonable to suppose a person will try to choose words that will mean what he wants them to mean to his target audience, then it is reasonable to suppose that how his target audience understands his words is evidence for what their speaker meant. And what better way to tell what his target audience understood his words to mean than to check out what they did after they heard his words, and why they said they were doing it?
The 'prosecution' in Trump's trial is going to be very grateful for all those videos of the terrorists in action, etc. But here's something you might not know yet. The prosecution will also have available to them all those local TV station interviews of the terrorists conducted in the days following 1/6. Add to that whatever they have captured of the internet chat room traffic in the months leading up to 1/6. So much of that will be relevant to establishing the case that Trump's words meant go storm the Capitol Building, hang Mike Pence, shoot Nancy Pelosi, etc.
Back to Jesus. Basically the same principle can be applied here to the task of determining what Jesus meant when he said "love your neighbor".
And if what I said here is not enough, then there is another way of logically arguing for essentially the same conclusion. That way was pointed back in the late 1800s by Charles Sanders Peirce, who logicians sometimes call "the greatest logician America has produced".
In my opinion that second way requires a little more work to understand, but it is also more compelling once understood,
I hope this has helped to answer your question.
