the Bible tells me so

"Most of the people in nut houses are religious because most Americans are religious," said Rodney Stark, a social sciences professor at Baylor University. "We know what causes schizophrenia and it isn't going to church. It's biochemical." ....in some fundamentalist environments, symptoms of mental illness can appear normal: Obsession over a religious leader can be interpreted as religious fervor, and delusions can be interpreted as religious visions....while religion doesn't cause mental illness, he believes existing conditions can be inflamed by religious environments where leaders demand absolute obedience and claim to speak for God. People with schizophrenia, personality disorders and a host of other mental disorders may be drawn such faiths for their structure, he said. "This kind of culture, religious atmosphere, group dynamic can set up a situation where that person is more likely to act out in aggressive ways under tremendous pressure," Olson said.

...read it all: Moms who kill children have religion in common

Genesis 22:

Then God said, "Take your son, your only son, Isaac, whom you love, and go to the region of Moriah. Sacrifice him there as a burnt offering on one of the mountains I will tell you about."