Wikipedia
A Covenant-breaker or the act of Covenant-breaking is a term used by Bahá'ís to refer to a form of disunity: "The specific mission of Bahá'u'lláh relates to world unity. Since it would be impossible for the Bahá'í Faith to unite the world if it were itself disunited, the role of the covenant as the guarantor of the unity of the Bahá'í community becomes inextricably linked with the goal of world unity: "It is evident that the axis of oneness of the world of humanity is the power of the Covenant and nothing else." (TDP 49, cf GPB 239, SWA 208-9). Being declared a Covenant-breaker is done by the head of the Faith — which is the Universal House of Justice, which has nine members and is the governing body of the Bahá'ís since 1963. Bahá'ís avoid association with Covenant-breakers, even if they are a family member.