Genesis 4:19
And Lamech took unto him two wives: the name of the one was Adah, and the name of the other Zillah.
Cross-reference
Genesis 2:24
Contrast
In Genesis 2:24, one man and one woman become one flesh. Lamech's two wives directly violate this one-flesh principle.
Genesis 2:18
Contrast
In Genesis 2:18, God provides one helper suitable for man. Lamech taking two wives departs from that original design.
1 Samuel 1:2
Parallel
In 1 Samuel 1:2, Elkanah also has two wives, echoing the same practice and foreshadowing the household tensions it creates.
2 Chronicles 24:3
Parallel
In 2 Chronicles 24:3, Joash also has two wives — another biblical instance of the polygamy Lamech here pioneers.