Thus nations and states with all their strength could not resist Him [Baha’u’llah]. Verily, single and alone, imprisoned and oppressed, He accomplished whatever He desired.
I do not wish to mention the miracles of Bahá'u'lláh, for it may perhaps be said that these are traditions, liable both to truth and to error, like the accounts of the miracles of Christ in the Gospel, which come to us from the apostles, and not from anyone else, and are denied by the Jews. Though if I wish to mention the supernatural acts of Bahá'u'lláh, they are numerous; they are acknowledged in the Orient, and even by some non-Bahá'ís. But these narratives are not decisive proofs and evidences to all; the hearer might perhaps say that this account may not be in accordance with what occurred, for it is known that other sects recount miracles performed by their founders. For instance, the followers of Brahmanism relate miracles. From what evidence may we know that those are false and that these are true? If these are fables, the others also are fables; if these are generally accepted, so also the others are generally accepted. Consequently, these accounts are not satisfactory proofs. Yes, miracles are proofs for the eyewitness only, and even he may regard them not as a miracle but as an enchantment. Extraordinary feats have also been related of some conjurors.
Briefly, my meaning is that many wonderful things were done by Bahá'u'lláh, but we do not recount them, as they do not constitute proofs and evidences for all the peoples of the earth, and they are not decisive proofs even for those who see them: they may think that they are merely enchantments.
Also, most of the miracles of the Prophets which are mentioned have an inner significance. For instance, in the Gospel it is written that at the martyrdom of Christ darkness prevailed, and the earth quaked, and the veil of the Temple was rent in twain from the top to the bottom, and the dead came forth from their graves. If these events had happened, they would indeed have been awesome, and would certainly have been recorded in the history of the times. They would have become the cause of much troubling of heart. Either the soldiers would have taken down Christ from the cross, or they would have fled. These events are not related in any history; therefore, it is evident they ought not to be taken literally, but as having an inner significance.
Our purpose is not to deny such miracles; our only meaning is that they do not constitute decisive proofs, and that they have an inner significance. (Abdu'l-Baha, Some Answered Questions, p. 36)