Matthew 22 opens with a parable of a marriage feast, and it's a pretty strange parable once again. It almost makes sense (well as much sense as you can expect from a parable) until you get down to verse 11, at which point there is some guy without a "wedding garment" which I'll venture to guess meant that he wasn't dressed up properly for the occasion. But then, these guests were just a bunch of random people called in from off of the street, if we're to understand the story, so...? I have to admit, this one has always stumped me on the face of it. There's a symbolic aspect that almost makes sense, but it involves reading in a lot that really isn't there. See, there's this theological concept that when we are saved, our unrighteousness is removed from us, and we become clothed with the righteousness of God, and so it might seem that perhaps this guy accepted the invitation, but thought he could get into the party on his own merits, despite being just some guy off the street. See, it only just barely makes sense of it, and it involves bringing in a lot of theological baggage; it probably was a waste of space and I should just left it, but that's the luxury of blogging I guess: waste as much space as you care to, and just move on. (I've addressed the existence of Hell in Matthew 10 as deeply as I care to, so I'll drop that link and move on.)
After this parable comes the famous story of Jesus being asked whether or not one should pay taxes. There's a lot of interesting material here. Note that the Pharisees and the Herodians (who usually hated each other) were working together to trick Jesus. Note that it was a trick, and that a simple answer of "No" would be considered insurrection against Rome, while a simple answer of "Yes" would be denying the authority of Jewish nationalism. Also, although I'm pulling this from vague memory, note that the "image and superscription" on the coin were enough to make Roman coins quintessentially tiny pagan idols. Like the SAB, I think Jesus' answer is not only saying pay taxes, but that one should keep church and state separate (although it's not very clear as to which is which overall, but the concept stands, I think.)
Now the Sadducees--who were a religious group who didn't believe in an afterlife as the text says--come up to Jesus with a bizarre question that, while clearly made up, was also within the realm of possibility of Mosaic Law. Jesus skips over the whole question to point out that in the afterlife, there is no marriage. (It doesn't say no sex here, but it's not outrageous to imply it.)
Finally after all the tricky questions, someone simply asks him to name the greatest commandment, to which Jesus replies "Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind." and adds on the second-greatest, "Thou shalt love thy neighbour as thyself." which the SAB is happy to get on board with as being great, but asks then how should nonbelievers be treated? I may have skipped this before, but I think it's pretty straightforward most of the time. The section that says "Shun them" is not a problem, in my estimation. First of all, I think "Shun them" is an overstatement of what this verse it really saying, which is that you should avoid entering into legal contracts with them, but you can still love them while keeping yourself disentangled legally. It's the "Kill them" section that's clearly harder to deal with, duh. First of all, I don't think that this verse is saying that anybody who is an unbeliever should be treated this way, even in ancient Israel (which this is another verse that I think applies mainly if not only to that context). I think this is particularly for a person who believes in a strange religion and tries to convince others to follow him into that belief. So how does this fit into loving your neighbor? I suggest this: if following after strange gods is going to lead to ruin, then it is best that this sort of theological swindling should be dealt with the same way that purely physical swindling is dealt with. You have ways that you deal with a thief. You have ways that you deal with a murderer. Someone who is enticing people after false gods is a thief and a murderer of people's souls, and should be dealt with seriously, at least in ancient Israel. Yeah, it sounds harsh, and it is, but I think it's for a reason.
The last issue on this chapter is whether Jesus is the son of David. (Remember in Biblical language, this meant ancestor; Jesus was certainly not the actual son of David.) I think that the two verses in the "No" column are not Jesus saying "No", but rather pointing out to those within hearing that the actual relationship between the Messiah and David was a complicated one, and not as simple as just a mere ancestral one. Jesus may be the son of David, but he's greater than David all the same.