When the LORD gets an idea in his head he's like a dog with an old sock, you just can't get it away from him. I like his wording here: "the preaching that I bid thee," like "As I was saying before I was interrupted." That preaching that I bid thee that one time, Jonah, remember? I know you do, so I'm not even going to bother to repeat it. Of course, in a few verses we're going to see the preaching and then it will become clear how easy it was to remember.
Now's a good time to point out that Jonah is identified as the son of Amittai, whose name means "truth." I have seen it suggested that this wording is an indication of Jonah's character: he is inflexible, believing only in right and wrong, and unconcerned with trifling questions of mercy or fellow-feeling. The Ninevites are bad: God should smite them. Simple! But wrong. Use every man after his desert, and who should scape whipping? Jonah, for example, the only prophet out of the scads presented in the Bible to defy the direct command of God, does not get used after his desert; rather God keeps snatching him back, hoping he's learned his lesson, just as he hopes the Ninevites will learn theirs. Perhaps Jonah takes this as his due because he's a Hebrew: perhaps he thinks he can get away with cutting class because he's the teacher's pet, and the idea of the Ninevites' getting the same mercy enrages his sense of deserved privilege. What do you mean you canceled class the day I decided to cut? That's not fair! I'm the son of Truth, and they're just a bunch of Iraqis!
I think the most important moral of the Jonah story is an exhortation to be compassionate toward each other as God is compassionate toward us. Maybe the name of Jonah's father gives us a slight variation on this lesson: when you find yourself thinking you're the sole heir to truth, you should take a close look at how you treat other people. Or you might end up regurgitated by a fish onto the Israeli Coastal Plain. I can think of a few public figures who could stand to have that done to them.