So after Sarah is dead, Isaac must be nearly 40 by this time, and yet he hasn't married yet. What's he waiting for? Apparently, his father has some misgivings about his son marrying one of the local Canaanite women, a fact that the SAB labels as "Intolerance". This is easy to address on a factual level, but difficult on other levels, as people have different views on whether this sort of thing is acceptable. The Canaanites were pretty much pagans, and Abraham wasn't going to let his son take a pagan wife. There are numerous stories in the Bible of Israelite men marrying pagans and being led astray to wrong religious practices. No doubt this comes from the fact that most of us men find our sexual desires to be one of the most powerful forces in our life, and sexuality is something that is closely mingled with spirituality on numerous levels. I suppose one could say it's intolerant, but from a Judeo-Christian point of view, there are some sorts of intolerance that are not only acceptable, but good. Really, most people are intolerant about something; in our modern highly-tolerant culture, there are a lot of people who are intolerant towards intolerance!
So, Abraham admits that he's not likely to live too much longer, and to deal with the matter of his son still being unmarried, he makes Eliezer swear that he will get Isaac a bride from among his family back in his homeland. This is a very interesting oath, as Eliezer is asked to "put his hand under the thigh of Abraham," which--as the SAB points out--is likely to be a euphemism for holding Abraham's genitals. Apparently, this was a surprisingly common way for a man to take an oath in those days, and in this case, as the oath is concerned with the carrying on of Abraham's offspring, it seems symbolically appropriate. (As for the moral value of swearing an oath, I discussed it at the end of this post.) Eliezer seems concerned that he might not be able to just run off and get a wife like that, and suggests that he bring Isaac with him, but Abraham insists that Isaac is not to go back, and tells Eliezer if he can't work it out, then he's not bound by the oath any more.
Now when Eliezer gets to where he's supposed to go, and he prays to God that a very specific sign will be given to him, which comes to pass. This sign of Rebekah giving water to Eliezer's camels is actually a fairly significant one, as a camel drinks a lot of water, and for someone to give water to ten camels "until they have done drinking" is quite a task. In addition to being an answer to Eliezer's prayer, it shows that Rebekah is a strong, healthy woman with a kind heart. She's also noted to be attractive, which the SAB puts some icons next to, but essentially no comment, so I don't know what the issue is there.
So Eliezer, being convinced that Rebekah is the woman that God wants Isaac to marry, gets introduced to her family (Isaac's cousins), brags a lot about how many slaves Abraham has (I discussed the morality of slavery here), and gives Rebekah some gold bracelets and an "earring". I didn't realize that the KJV translated this "earring". Most other translations, probably because of the wording of verse 47 ("put the earring upon her face") translate the jewelry given to her as "nose ring". I've always thought it was odd with the popularity of nose rings these days that I never hear of anyone in modern times giving a nose ring as an engagement ring. It sounds cute to me.
Eliezer takes some time to recap for these folks everything that's happened to Abraham, excessive repetition being for better or worse a common Biblical narrative device. At the end, Rebekah's family agrees that Isaac would be a good husband and that it seems to be God's will for her to go, so he showers them all with gifts and insists he return the very next morning. Sort of a neat and unexpected thing happens here in the midst of a lot of stuff that sounds rather sexist: Eliezer wants to go at once, her parents want her to wait a few days so they can see her off, and in the end they let her make the decision. She decides to go, and the rest is history.