"Concerning your question relative to the duration of the Baha'i
Dispensation. There is no contradiction between Baha'u'llah's statement in
the Iqan about the renewal of the City of God once every thousand years,
and that of the Guardian in the Dispensation to the effect that the Baha'i
cycle will extend over a period of at least 500,000 years. The apparent
contradiction is due to the confusion of the terms cycle and dispensation.
For while the Dispensation of Baha'u'llah will last for at least one
thousand years, His Cycle will extend still farther, to at least 500,000
years.
"The Baha'i cycle is, indeed, incomparable in its greatness. It includes
not only the Prophets that will appear after Baha'u'llah, but all those
who have preceded Him ever since Adam. These should, indeed, be viewed as
constituting but preliminary stages leading gradually to the appearance of
this supreme Manifestation of God."