The Bab said that whenever “He whom God will make
manifest” appears, accept Him. He never said don’t accept
Him until after the lapse of 1000 years. Also Baha’u’llah says
that in the year 9 of the Babi Dispensation the time was ripe
for the Revelation of “He whom God will make manifest”.
As the Bab was not only a Manifestation but a Herald of this
Baha’i Faith, the interval between His Revelation and that of
Baha’u’llah was of shorter duration. His Dispensation in a
sense will last as long as Baha’u’llah’s lasts.