"O lord of believers, tell us of Hazrat Mahdi (as): And the lord of believers (saas) said:  "Generations will pass and believers will decline in number, and the seekers of truth and supporters of faith will depart, then he [Hazrat Mahdi (as)] will come... He [HAZRAT MAHDI (AS)] will water a world consisting of oasis and [the Qur’an] is a boundless ocean.”
 
(Kitab al Ghaybat, [Bihar al-Anwar, Vol. 51], Ansariyan Publications, collected by: Muhammad Baqr al-Majlis, Iran-Qum, 2003, p. 184.


This hadith narrated from our Prophet (saas) says that Hazrat Mahdi (as) will have a global impact following his coming. Hazrat Mahdi (as) will disseminate the Holy Qur’an likened to a boundless ocean, to the whole world and will cause the moral values of the Qur’an to be adopted and prevail among people. The hadith expresses Hazrat Mahdi’s (as) success in causing the moral values of the Qur’an to be adopted across the world with the customary perfection of the language of our Prophet (saas).