A Counterquestion

In my morning reading, I thought about Matthew 19: 3-9.  Here the Pharisees thought they'd get Jesus with the same subject that caused the demise of John the Baptist--divorce.  John condemned Herod Antipas for divorcing his wife and marrying his brother's wife, Herodias.  It was Herodias' scheme that resulted in John's death.

But Jesus turned the tables.  He quotes Genesis 19: 4-5--the Torah.  Shouldn't the Pharisees have known this?

Marriage is God's creation.