"fishers of men” and now: "quickeners of mankind”

The Revelation associated with the Faith of Jesus Christ focused attention primarily on the redemption of the individual and the molding of his conduct, and stressed, as its central theme, the necessity of inculcating a high standard of morality and discipline into man, as the fundamental unit in human society. Nowhere in the Gospels do we find any reference to the unity of nations or the unification of mankind as a whole. When Jesus spoke to those around Him, He addressed them primarily as individuals rather than as component parts of one universal, indivisible entity. The whole surface of the earth was as yet unexplored, and the organization of all its peoples and nations as one unit could, consequently, not be envisaged, how much less proclaimed or established. What other interpretation can be given to these words, addressed specifically by Bahá'u'lláh to the followers of the Gospel, in which the fundamental distinction between the Mission of Jesus Christ, concerning primarily the individual, and His own Message, directed more particularly to mankind as a whole, has been definitely established: "Verily, He [Jesus] said: 'Come ye after Me, and I will make you to become fishers of men.' In this day, however, We say: 'Come ye after Me, that We may make you to become the quickeners of mankind.'" 
- Shoghi Effendi  ('The Promised Day is Come')

The amazing spiritual transformation of Peter

"Peter," 'Abdu'l-Bahá has testified, "according to the history of the Church, was also incapable of keeping count of the days of the week. Whenever he decided to go fishing, he would tie up his weekly food into seven parcels, and every day he would eat one of them, and when he had reached the seventh, he would know that the Sabbath had arrived, and thereupon would observe it." If the Son of Man was capable of infusing into apparently so crude and helpless an instrument such potency as to cause, in the words of Bahá'u'lláh, "the mysteries of wisdom and of utterance to flow out of his mouth," and to exalt him above the rest of His disciples, and render him fit to become His successor and the founder of His Church, how much more can the Father, Who is Bahá'u'lláh, empower the most puny and insignificant among His followers to achieve, for the execution of His purpose, such wonders as would dwarf the mightiest achievements of even the first apostle of Jesus Christ! 
- Shoghi Effendi  ('The Advent of Divine Justice')