What happened in the tent of Noah? There are many theories about this, but I am not sold on the idea that, in the case of Noah/Ham, the "uncovering the nakedness of the father" is a euphemism for Ham committing incest with his mother (or, as others theorize, raping his own father). Yes, in some cases, “uncovering the nakedness of someone” is the Bible’s euphemism for incest. The weakness of that interpretation in Genesis 9, however, is that the other brothers walk in backward so as not to see the nakedness of their father. Thus, we are dealing here with a drunk, naked Noah, not incest or rape. I know that there are still unanswered questions about this whole strange story, but at least as far as the nudity is concerned, it means that literally not metaphorically.
Why was Canaan cursed instead of Ham? This question is one of those interpretive OT knots that is hard, if often impossible, to untie. Of course, theories abound. Some say Canaan participated in the sin of his father, Ham, but is unnamed. Some Jewish scholars suggest an ellipsis, so that we should read “cursed be [the father of] Canaan.” I lean toward seeing it as a case of Noah speaking prophetically, so as to suggest that Ham's descendants -- the Canaanites, named after Canaan, of course -- would come to embody the worst instincts of their forefathers. In the end, no one knows for sure. It's one of those "wait for the heavenly school" to find out the full answer.
I don't know of any other biblical reference similar to what the brothers did, nor any biblical or ANE references to it being a taboo to see (especially on accident) one's father naked. The main weakness that I see in other explanations (Ham castrated Noah, Ham sodomized Noah, Ham committed incest with his mother) is that they import material not found in Genesis in an effort to explain the gravity of the offense and the subsequent curse. While I understand this impulse, I think it goes way too far in seeking an explanation. And I readily admit that my traditional, conservative view (often called "voyeurism," though that term seemed infelicitous here) is far from completely satisfactory. But I am fine with saying, in the end, there is much that we do not know, cannot know, and do not understand about what happened that day.
Written by Chad Bird, 1517 Scholar