I just finished reading The Strange Case of Doctor Jekyll and Mr. Hyde, by Robert Louis Stevenson. It may have been published in 1886, but it's lessons hold true today.

Dr. Jekyll thought he could use science to divorce himself from the dark side of his nature - that by doing so, he might be relieved of the necessity to struggle against it. He thought he could embrace evil for short periods, the way one puts on a coat on a cold day, and then discard it by returning to his good self - unchanged. In the end, he was consumed by the very evil he thought he could control.

What a powerful lesson. We cannot toy with evil and be unaffected by it. It will destroy us. We cannot embrace corruption without being corrupted ourselves. Instead, we must steadfastly resist evil at every turn and without compromise, lest we follow in the footsteps of Dr. Jekyll and be destroyed.