The SAB doesn't have much to say about chapter 40, but let's see what we have here, because it's a bit of a turning point in Joseph's life. One of the things I find interesting here, as I mentioned back in chapter 37, is that Joseph, for being such a supposed expert at interpreting dreams, never bothered to interpret his own (or if he did, it's not mentioned).
While Joseph is spending his time working away in prison, two men come to be interred with him, both servants of Pharaoh. One is the royal baker, and the other, while called a "butler" in this translation is really more of a wine steward or cup bearer, which is clear enough from the context anyway. It's been interpreted by some, and it makes sense, that these two men may be suspects in a criminal matter, and they are being held in jail until the matter is cleared up. Thus they both go in together and come out together, being implicated for the same crime. This is another interesting moment which is often thought as being symbolic of the Eucharist, these two men representing bread and wine.
In any case, the two men each have a dream, and the two dreams are similar. They both involve the dreamer going back into service for Pharaoh in an odd, supernatural fashion, and also both involve the number three. (Note that in each instance of Joseph dealing with dreams, there are two dreams that have an important number (12, 3 and 7) which is the same in both.) The butler/cupbearer's dream is a pleasant one, and the interpretation is pleasant. The baker's dream is an unpleasant one, and the interpretation is rather unpleasant. In both instances, Joseph uses a variation of the phrase "Pharaoh shall lift up thy head"; in the butler's case, the idiom means "Pharaoh will show you favor" while in the baker's case, the addition of "from off thee" indicates that the baker is going to be executed by beheading. When the interpretations come true (which they do), Pharaoh "lifted up the head of the chief butler and of the chief baker", which in this case means that he singles them out for special treatment. I love the way the Bible plays with words, in this case showing the flexibility of a simple idiom.
The SAB apparently finds Pharaoh's treatment of the baker to be cruel and/or violent. Actually, the KJV understates it a bit, as it's likely that what is really going on here is not that the baker was put on a gallows, but rather that he was beheaded, and his body and/or head was impaled on a spike for the birds to eat. So yeah, it is a bit violent and cruel. I find it interesting that the SAB has no issue with the fact that Joseph was able to predict the future.
I want to add a final note here about a minor point in language that also covers an issue I have heard elsewhere, although don't see mentioned in the SAB. The butler/cupbearer fails to "remember" Joseph after he's restored to his position. This word for "remember" is used many times in reference to God, perhaps most well-known and notably in Genesis 8:1 and Exodus 2:24. Some people have wondered, "If God is 'remembering' Noah or the Israelites, does that mean he had 'forgotten' them?" Not at all. The word that the KJV prefers to translate as "remember" has different shades of meaning, one of which is the second-most preferred translation: "mention" (v. 14, same word in Hebrew). The general idea is that when one "remembers" something, it is brought to the full attention. Joseph is saying, "Make sure Pharaoh knows about me and gives some attention to my wrongful imprisonment!" In the many cases where the Bible says God "remembered" something, the idea is that God decided to turn his full attention to dealing with a specific problem, because its time had come. Joseph was forgotten for two years, but frankly, his time had not yet come.