In Alma 7, he’s visiting the people in the land and city of Gideon. He goes hoping they won’t have the same problems as the people at Zarahemla did. He’s happily rewarded, to find them a righteous and good people. He takes the opportunity to instruct them further, since righteous people are naturally hungry for the word.
In verse 23 he tells them (emphasis added):
23. And now I would that ye should be humble, and be submissive and gentle; easy to be entreated; full of patience and long-suffering; being temperate in all things; being diligent in keeping the commandments of God at all times; asking for whatsoever things ye stand in need, both spiritual and temporal; always returning thanks unto God for whatsoever things ye do receive.
This is where we get the incorrect phrase “moderation in all things.” Moderation in all things would mean we’d purposely include a healthy dose of wickedness, alongside only lukewarm righteousness. “Temperate” specifically applies moderation to appetites and passions that are actually a good thing, in moderation (Webster’s and the OED confirm the limited scope of “temperate”).
So “temperate in all things” specifically refers to things like eating, sleeping, physical intimacy, etc. All are good things when we’re moderate in them. In Alma’s time and location, it probably also referred to drinking alcoholic beverages as well.
Maybe this could also apply to “natural high’s” like runner’s high, or other adrenaline/endorphin highs. Or even spiritual highs that can come from doing good things. We probably don’t want to be the person who works out 4hrs a day, or as we’ve been warned, who over-emphasizes one aspect of the gospel above all others. See my previous post about this as exemplified by Zeniff. Also a quote from Elder Maxwell that was pointed out in the comments of that previous post:
How important it is to the symmetry of our souls that we interact with all the gospel principles and with all the Church programs, so that we do not become so highly specialized that, if we are deprived of one source of satisfaction, indeed we are in difficulty. It is possible to be incarcerated within the prison of one principle. We are less vulnerable if our involvements with the kingdom are across the board. We are less vulnerable if we care deeply about many principles—not simply a few.
So “temperate in all things” makes much more sense than “moderation in all things.” It conveys the idea of not being extremist in necessary and important things, that are good. The key is realizing that they’re only good as long as they’re done in moderation. In some ways it’s easiest to slip from temperance to extremism in these areas, specifically because they are sanctioned by God. Alma and other prophets have made it clear that they’re only sanctioned by Him, when done in temperance and with balance.
That theme flows throughout this verse though. He’s encouraging them to be humble, submissive, gentle, easily taught or coached, patient, long-suffering, temperate, diligent. Temperate just fits right in there, doesn’t it?