I don't think it's clear that the Incident In The Temple With The Whip was (or: was meant to be understood as) a matter of temper-losing. It could, again, be read as a deliberate statement, an invocation of (e.g.) the old prophecy about "purifying the sons of Levi", done deliberately to make a point.

I'm beginning to wonder if we don't perhaps ascribe subtly different definitions to the phrase "losing one's temper".

I wonder that because I don't think that the two options that you present here - that of temper-losing, and that of deliberate action - are necessarily contradictory.

Thinking about it, I am defining having lost one's temper as a state wherein one sounds audibly angry, has a tendency to select sweeping, destructive actions when attempting to reach one's goals, has very little patience with others and is likely to shout at people, but retains full control over one's actions and can do things quite deliberately.

It may be that you are thinking of a yet angrier state, where one loses control and just lashes out at random. While that would also be losing one's temper, that wasn't what I'd meant by the phrase earlier...

In other words, yes, I agree that the Incident In The Temple With The Whip was most likely a deliberate statement. I just don't think that that invalidates anything I said in my previous comment.

(Incidentally, an earlier edit of my paragraph about "the character of Jesus as generally understood by Christians" said explicitly something like "Of course being good isn't quite the same as being nice, and I'm not claiming otherwise". Though, as it happens, my own conception of goodness does involve being nicer than Jesus is shown as being in many stories in the gospels, and also nicer than I find it plausible to believe any super-powerful being actually is, given the state of the world. I mention this not in order to start an argument about the credibility of Christianity, but to calibrate the extent to which I agree with you that Christians needn't regard Jesus as "nice".)

Noted.

While we could try to narrow down exactly to what extent each of us considers "good" and "nice" to overlap, I think we're more-or-less in agreement on the main point here; that Jesus, as presented in the Bible, could be good all the time without necessarily being nice all the time (and sometimes, indeed, could be good at the expense of being nice).