I found this quote from a google books word search:
“He also represents it to them as a selfevident principle, that he who is joined in affection and criminal conversation to an harlot, is one body with her. “What! know ye not that he which is joined to an harlot is one body? for two (saith he) shall be one flesh” (John Colquhoun, sermons, chiefly on doctrinal subjects).
Self-evident principle, Colquhoun says. Correct. Paul writes as if sex constituting marriage was a self-evident principle, evinced by his question and citation of Genesis 2:24. For more on this subject see the following: