The subject is taken from Genesis 9: 20-27. Tired and inebriated, Noah lay in his tent and slept after drinking too much wine. His son Ham approached him and, seeing his nakedness, called his two other brothers, Shem and Japeth. Walking backwards so that they could avoid seeing their father naked, they laid a cloak over him. When Noah awoke and found out what had happened he lay a curse on Ham's son Canaan.