This article discusses the argument that marriage cannot be undone because husband and wife are one flesh. The author looks at the passages concerned with "one flesh": Genesis 2:23-24, Leviticus 18, Leviticus 21, and Deuteronomy 24:1-4 from the Old Testament, and then 1 Corinthians 6:15-18 and Ephesians 5:31 from the New Testament.