Why did Noah curse Canaan? In order to explain it, I need to reiterate the story itself.
In Genesis 9, it says that Ham, Canaan’s father saw Noah’s nudity, and Noah cursed Canaan as a consequence. Then Canaan proceeded to lead the Canaanites, Israel’s enduring adversaries.
On the surface, the story seems whimsical, unlike the more believable history in the book of Genesis. So let’s take a closer look. An often-used biblical rhetorical expression is used throughout Canaan’s tale, and the significance of the story becomes compelling when reread by Christians with a clear understanding of this phrase and its meaning.
Ancient Hebrew uses the phrase “a man’s nakedness” to infer sexual intercourse with his wife. As Moses stated in Leviticus 20:11,
“And the man that lieth with his father's wife—he hath uncovered his father's nakedness—both of them shall surely be put to death; their blood shall be upon them.”
Canaan was cursed because he was created in an act of incest. The story reminds its readers that Canaan’s father is Ham, not Noah. Noah’s curse on Canaan was not anger or an evil spell, but rather acknowledgment of cause and effect. Canaan’s unfortunate circumstances act as a cautionary tale to warn others against repeating Ham’s mistake of “seeing his father’s nakedness”, which is to say, conceiving a child in incest. Then Genesis proceeds to present the foundation of the conflict concerning the Canaanites and the Jews.