Megachurch Pastor Rick Warren sparked controversy on social media, Thursday, with a tweet forgiving the person who sold his son Matthew a gun. 27 yr old Matthew, Warren says, used the gun to kill himself, last weekend. The Orange County Coroner’s Office confirms the younger Warren died of a self inflicted gunshot wound. Authorities say the gun’s serial number was scratched off, which is a federal offense. CBS News reports it is illegal in California to buy a gun without a background check. Before committing suicide, Matthew Warren suffered from mental illness, according to his family.