Isaac and Rebecca's son, Esau, married two pagan Hittite women, who were a source of agony to his parents, because they indulged in idol worship.
The Midrash says that Isaac was more distressed by the pagan rituals than Rebecca, because Rebecca grew up in the home of her father, Laban, who was an idol worshipper. Having been exposed to pagan rites in her childhood, Rebecca was not as provoked as Isaac, who grew up in the saintly home of Abraham.
Although Rebecca was a holy, pious woman who detested paganism and idol worship, she was not as deeply affected by them because she had been exposed to them. We can lose our odium of abominable behavior if we are exposed to it.
Our children are exposed to much violence on TV. Regardless of their knowledge that violent behavior is wrong, they are not emotionally turned off by it.
We must be cautious about what we can become accustomed to.