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.
Covenant-breaking does not refer to attacks from non-Bahá'ís or former Baha'is. Rather, it is in reference to internal campaigns of opposition where the Covenant-breaker is challenging the unity of the Faith, causing internal division, or by claiming or supporting an alternate succession of authority or administrative structure. The central purpose of the covenant is to prevent schism and dissension. In a letter to an individual dated 23 March 1975, the Universal House of Justice wrote:
When a person declares his acceptance of Bahá'u'lláh as a Manifestation of God he becomes a party to the Covenant and accepts the totality of His Revelation. If he then turns round and attacks Bahá'u'lláh or the Central Institution of the Faith he violates the Covenant. If this happens every effort is made to help that person to see the illogicality and error of his actions, but if he persists he must, in accordance with the instructions of Bahá'u'lláh Himself, be shunned as a Covenant-breaker.
The term 'Covenant-breaker' or, in Arabic 'naqid al-mithaq' [pl. Naqidu 'l-mithaq], was first used by `Abdu'l-Bahá to describe the partisans of his brother Mírzá Muhammad `Alí, who challenged his leadership. In `Abdu'l-Bahá's Will and Testament, He appointed Shoghi Effendi as the Guardian of the religion and called for the eventual election of the Universal House of Justice, and defined in the same manner opposition to these two institutions as Covenant-Breaking. `Abdu'l-Bahá advised all Bahá'ís to shun anyone opposing the Covenant: "...one of the greatest and most fundamental principles of the Cause of God is to shun and avoid entirely the Covenant-breakers, for they will utterly destroy the Cause of God, exterminate His Law and render of no account all efforts exerted in the past."