In Matthew 19, verses 4-10, the SAB brings up some questions regarding marriage. Hopefully, I've already answered these elsewhere, let me see. Is marriage a good thing? I addressed this largely in Genesis 2, at which time I said that for most people, being married is a great thing, but Paul happens to point out that as good as it is, marriage complicates life, and one should be careful to think about the implications of that sort of commitment before entering into it. I addressed polygamy most fully on this page, where I said that I don't think polygamy is a sin, but it's far from a desirable state of affairs, usually leading to trouble. What about divorce? I addressed that back in chapter 5, and it's worth noting here that the SAB puts verses 6 and 9 in separate categories; as I've said before, an apparent contradiction that follows so quickly is usually (in my opinion) an indication that one is not understanding the real meaning of the passage: verse 9 is further clarification on verse 6, not a contradiction.
Following this, Jesus has some cryptic things to say about eunuchs in verse 12, and while I don't really know what it's about, I can give some speculation and response to the SAB's speculation. The idea presented that perhaps Jesus is talking about homosexuals is a thought provoking one; I myself had once considered that possibility that this verse was referring to transsexuals, after all, there do exist genetic disorders in which a person does not develop functional genitals. On the other hand, people who "have made themselves eunuchs" does seem to suggest self-castration, but if I can appeal to hyperbole again, it may be that he is referring to people who have taken a vow of celibacy, which doesn't seem too far of a stretch. (This would imply that those who were "born eunuchs" are people with no natural sexual drive, a concept not unheard of.) The SAB links to two pages that are almost identical (and neither of which mention the eunuch from Acts 8, who might be considered noteworthy) to ask what God may feel about castration, both of which hinge on Deut. 23:1 which says that a man with wounded genitals "shall not enter into the congregation of the LORD." I really should do some more research here, and I'm surprised I haven't covered that phrase already. One thing I'm fairly sure it does mean is that such a man cannot serve as a priest in the temple. I don't believe it means that such a man cannot be a practicing Jew (and that is an important distinction, as we're now talking about the N.T. church, not the O.T. "congregation"). I suspect that the distinction is that such a person cannot perform any religious duties, which even non-priests perform at times. (If Jesus is speaking in hyperbole, none of this matters, of course.)
The bit about children was already covered in the previous chapter, and while each of the particulars of verse 17 have been covered, it's an odd verse that deserves some special attention. Jesus says "Why callest thou me good? there is none good but one, that is God." Jesus seems, as the SAB claims, to be saying that he is not neither good nor God, so what's going on? I seem to vaguely remember hearing before that it was the belief of the Pharisees that "good" was an adjective that could only rightfully applied to God; whether this was the case, I don't think it's too much of a stretch to say that Jesus is cautioning this guy to think twice before applying labels to people and things, even if he happens to be right.
Now the exchange that happens after this is one that's repeated in the other Gospels, and is a source of some contention, even outside of the SAB. Is Jesus really saying that the way to be saved is to keep the commandments? While the consensus is no, there is a strain of thought among Christianity that since Jesus said it, he must have really meant it, so what is the implication? (And the fact that Jesus is shown as listing a different set of commandments in each telling is once again something I think of as being of minimal importance; he was just tossing out a few, not making an exhaustive list.) Well in the case of this guy, Jesus shatters this guy's hope by telling him to give away all of his possessions to the poor. It's been said (even in the Bible) that the whole of the law can be summed up by "Love God with all your heart", and "Love your neighbor as yourself." If this guy couldn't give up all that he had, then he certainly loved money more than God, and he also surely wasn't able to love his neighbor as himself. (As for finer points on stealing and killing, I covered those in Exodus 20.) Jesus may be saying that you could go to heaven IF you could keep all the commandments, but that's an awfully big IF.
Is it OK to be rich? This can be a sticking point in the Bible, and I think the answer is subtle. I don't think the Bible ever outright says that wealth is a sign of wickedness, but rather shows awareness of that saying that to whom much is given, much is expected. If you're a good, honest, and hard-working person, wealth will probably come to you, but once you have it, God will expect you to use your wealth for good things. Sure there are a lot of rich people who are greedy bastards, but I personally have known people with six and seven-figure incomes who are some of the most generous and kind people you'd ever know. I think the N.T. verses the SAB gives, especially the one here in Matthew, are pointing out the danger of the love of money.
The question of whether God can do anything was addressed in Genesis 18. The issue of the apostles sitting on 12 thrones is not something I've ever addressed, although I recently asked a pastor his opinion on the matter (In the context of Revelation 4) and he suggested that rather than Judas Iscariot, Paul might be sitting on one of the thrones mentioned. Lastly, I don't think that verse 29 is suggesting that people should give up their wives and children, but rather that if they end up having to because of following Jesus, they will get something better as a reward.