Infallibility of the Prophets
Baha'u'llah teaches that everyone endowed with the Station of Prophethood is given sufficient proofs of His Mission, is entitled to claim obedience from all men and has authority to abrogate, alter or add to the teachings of His predecessors. In the Book of Iqan we read: (81:4)

How far from the grace of the All-Bountiful and from His loving providence and tender mercies it is to single out a soul from amongst all men for the guidance of His creatures, and, on one hand, to withhold from Him the full measure of His divine testimony, and, on the other, inflict severe retribution on His people for having turned away from His chosen One! Nay, the manifold bounties of the Lord of all beings have, at all times, through the Manifestations of His divine Essence, encompassed the earth and all that dwell therein.. (81:5)

And yet, is not the object of every Revelation to effect a transformation in the whole character of mankind, a transformation that shall manifest itself both outwardly and inwardly, that shall affect both its inner life and external conditions? For if the character of mankind be not changed, the futility of God's universal Manifestations would be apparent. - Kitab-i-iqan, pp. 14, 240. (82:1)

God is the One infallible Authority, and the Prophets are infallible because Their Message is the Message of God given to the world through Them. That Message remains valid until it is superseded by a later Message given by the same or another Prophet. (82:2)

God is the great Physician Who alone can rightly diagnose the world's sickness and prescribe the appropriate remedy. The remedy prescribed in one age is no longer suitable in a later age, when the condition of the patient is different. To cling to the old remedy when the physician has ordered new treatment is not to show faith in the physician, but infidelity. It may be a shock to the Jew to be told that some of the remedies for the world's sickness which Moses ordered over three thousand years ago are now out of date and unsuitable; the Christian may be equally shocked when told that Muhammad had anything necessary or valuable to add to what Jesus prescribed; and so also the Muslim, when asked to admit that the Bab or Baha'u'llah had authority to alter the commands of Muhammad; but according to the Baha'i view, true devotion to God implies reverence to all His Prophets, and implicit obedience to His latest Commands, as given by the Prophet for our own age. Only by such devotion can true Unity be attained. (82:3)

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