"Therefore, whosoever obeys the Center of the Covenant appointed by Bahá’u’lláh has obeyed Bahá’u’lláh, and whosoever disobeys Him has disobeyed Bahá’u’lláh."

"Inasmuch as great differences and divergences of denominational belief had arisen throughout the past, every man with a new idea attributing it to God, Bahá’u’lláh desired that there should not be any ground or reason for disagreement among the Bahá’ís. Therefore, with His own pen He wrote the Book of His Covenant, addressing His relations and all people of the world, saying, “Verily, I have appointed One Who is the Center of My Covenant. All must obey Him; all must turn to Him; He is the Expounder of My Book, and He is informed of My purpose. All must turn to Him. Whatsoever He says is correct, for, verily, He knoweth the texts of My Book. Other than He, no one doth know My Book.” The purpose of this statement is that there should never be discord and divergence among the Bahá’ís but that they should always be unified and agreed. In His prayers Bahá’u’lláh also said, “O God! Whosoever violates My Covenant, O God, humiliate him. Verily, whosoever violates My Covenant, O God, erase and efface him.” In all His Tablets, among which is the Tablet of the Branch, He has mentioned and explained the attributes and qualities of the Personage to Whom He referred in the Book of His Covenant. He has fully expounded the function and potency of that Personage, so that no one shall say, “I understand this from the writings of Bahá’u’lláh,” for He has appointed the Center, or Expounder, of the Book. He said, “Verily, He is the appointed one; other than He, there is none,” intending that no sects or prejudices should be formed, and preventing every man here and there with a new thought from creating dissension and variance. It is as though a king should appoint a governor-general. Whosoever obeys him, obeys the king. Whosoever violates and disobeys him, violates the king. Therefore, whosoever obeys the Center of the Covenant appointed by Bahá’u’lláh has obeyed Bahá’u’lláh, and whosoever disobeys Him has disobeyed Bahá’u’lláh. It has nothing to do with Him (‘Abdu’l-Bahá) at all—precisely as the governor-general appointed by the king—whosoever obeys the governor-general obeys the king; whosoever disobeys the governor-general disobeys the king."

`Abdu'l-Bahá, The Promulgation of Universal Peace, pp. 322-323 

16 September 1912 
(excerpt from) Talk at Home of Mrs. Corinne True 
5338 Kenmore Avenue, 
Chicago, Illinois

`Abdu'l-Bahá