Awoke from his wine is an idiom and means “to sober up” (Good News Translation), that is, to recover from his drunken stupor, or as New English Bible says, “awoke from his drunken sleep.” This is expressed naturally in one language as “When Noah woke up and his thinking was clear again….”

And knew means “learned” (Good News Translation), “found out,” “came to know.” How Noah learned the details of what had happened, the text does not say. It may be that he “heard the talk about what…,” as one translation says. What his youngest son had done to him refers to Ham’s failure to cover his father. Instead of doing this he had reported the matter to his brothers.

The expression youngest son is a problem, because the fixed order of names in 5.32; 6.10; 7.13; 9.18 seems to show that Japheth was the youngest son. Various explanations have been given, of which the most likely is that the writer of verses 20-27 followed a tradition that gave the names of the sons in the order Shem, Japheth, Ham, or Shem, Japheth, Canaan. But this problem is related to another problem that is just as difficult: why is the curse in the next verse directed against Canaan, when it was his father Ham who disgraced himself? See comments on verse 25.

Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Genesis. (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .