Lamech the First

The ideal marriage in the scriptures is between one man and one women as it says in Bereshit 2:24- "Therefore shall a man leave his father and his mother, and shall cleave unto his wife, and they shall be one flesh". Note the אשה(singular) not the plural form אשת. Its interesting to note that the first redefinition of marriage comes in 4:19,ff. when Lamech takes two wives. What seems to follow is a complete degradation of society that has to be destroyed in the flood.