The verses I would cite would be the law verses in Leviticus or Deuteronomy. The punishment for adultery was stoning while other sins required offerings for atonement. Theft required restoration of the stolen item plus 20%.(Lev 6:4,5).

Also the example of David's adultery with Bathsheba. The resulting child died, Bathsheba's husband was killed, and Davids family was not the same. If David had coveted her but not acted on his lust, things wold have been different and possibly not as severe.

What do you think?