A scorpion1 befriended a ladybug who became a loyal companionto him. A time came when she struggled to cross a challengingand dangerous river, and so the scorpion offered to take herto the other side on his back. He had come to care for herand promised he would never harm her. But, safely across theriver, he allowed his tail to dip upon her with its venomoussting. As she lay in greatest pain, she said, "… but, youpromised… why?" He shrugged2 and said, sadly, "Because it ismy nature." 
Regardless of our wishes, or even our intent, it is to our nature alone that we will be faithful. 