The Holy Prophet (Peace be upon him and his progeny ) said: Shall I not introduce a believer to you? A believer is the one whom other believers trust with their souls and wealth. Shall I not introduce a Muslim to you? A Muslim is the one from whose hand and tongue other Muslims are safe.... It is unlawful (Haram) for a believer to do wrong against another believer, or leave him/her in a lurch, or backbite against him/her, or suddenly reject him/her.