It is forbidden for the believers to have an extremely suspicious mind. Some kind of suspicions are indeed sins. Do not spy on each other [peeping into the neighbor’s house, opening one’s private letters, listening to the private conversations, etc.] and do not backbite one another [this is as detestable as eating your dead brother’s flesh]; is there any among you who would like to eat the flesh of his dead brother? Indeed none. Be mindful of God as He accepts the repentance; He is the Most Merciful.