Jami' at-Tirmidhi 2283

" Morning will come upon a man as a believer, who will be a disbeliever in the evening, and evening will come upon a believer, who will be a disbeliever in the morning" - he said: "Morning would come[upon a man] while his brother's blood, honor and wealth was sacred, and when evening would come, he would consider it lawful for him. And evening would come while his brother's blood, honor and wealth was sacred, and when morning would come, he would consider it lawful for him."