Chapter 3 starts very similarly to chapter 1. God calls Jonah to “Arise…” and go to Ninevah and, “…call out against it…” this time in the message God will tell him (instead of something about their evil coming to God’s attention, which was the last part of that same declaration in chapter, verse 2). This time, Jonah obeys.
Nineveh as a “great city” is kind of interesting. The ESV footnote has it saying, ”great city to God”, implying that it holds value to him in some way or another. That said, the rest of the sentence that footnote comes from talks about the size of the city itself and how long it takes to get across it. Not sure any of this makes a difference in the interpretation.
Only other thing to note is that being called a “great city” seems to imply eventual doom in the Bible as this reference is constantly being used to major earthly cities that are positioned against God. (See Revelation 11 for an interesting twist where Jerusalem is tagged with this distinction as well.) For references, see here: http://bit.ly/2v1Gisz
Jonah enters Ninevah and preaches the long and short of it: “40 days and Nineveh will be overthrown!”. Great, we think, he’s finally done what YHWH told him to do. But that’s not really what happened. We’re told that Ninevah is a 3 day’s journey but Jonah only goes a day in. He basically doesn’t go all the way to where the king is at to take the prophecy directly to him. He also doesn’t tell the people who will bring the prophecy to fruition (God, of course, but he doesn’t message it) nor does he provide any indication of what it would look like to repent. While God intends for a call to repentance, Jonah is mute on who (lest they try and petition YHWH to relent) and that there is even a chance for repentance. What looks likes obedience is not really that at all.
Either way, what Jonah ultimately proclaims is a call to destruction, Sodom and Gomorrah style. And the people receive it! I mean, they straight up accept the warning and believe it, calling for a fast, throwing on sackcloth (an indication of mourning and repentance) and turn from their ways. Even the king reacts to the same message, arising from his throne (notice his obedience in arising to mourn and repent in reaction to God’s word vs. Jonah’s failure to “arise” in similar obedience.)
We shouldn’t miss the reactions here as a whole. What you believe is reflected in what you do. When Jonah speaks, people believe God and mourn, repent and hope that God will relent so that they will not perish. There’s a consistent theme here of pagans/gentiles being concerned about people being saved compared to Jonah’s relative lack of concern for the matter. His obedience to God leads to their repentance, even if he did it begrudgingly, but we are probably well-served by the reminder that we are bearers of Good News (certainly more positively framed than what Jonah had to say) and people can be saved because of it.
And God does indeed relent, deciding not to destroy them in response to their repentance. Sounds like a good end of the story, except this story isn’t about the Ninevites really, it’s about Jonah (and likely Israel by extension). Thus we anticipate chapter 4.