In Genesis, Ham saw his father Noah uncovered after Noah became drunk.
Genesis 9:20–24 says Noah planted a vineyard, drank wine, became drunk, and lay uncovered inside his tent. Ham, identified as the father of Canaan, saw his father’s nakedness and told his two brothers outside.
Shem and Japheth responded by walking backward into the tent with a garment, covering Noah without looking at him. When Noah awoke and learned what had happened, the passage continues with a pronouncement involving Canaan.
This episode is often remembered inaccurately as a simple story about Ham insulting Noah, but the text specifically describes Ham seeing Noah uncovered and reporting it. Interpretations of the curse on Canaan have varied greatly, and later attempts to use the passage to justify slavery or racism are not supported as a neutral historical conclusion by the brief Genesis narrative itself.