Briefly, we say a universal cycle
in the world of existence signifies a long
duration of time, and innumerable
and incalculable periods and epochs. In
such a cycle the Manifestations appear
with splendor in the realm of the
visible, until a great and universal
Manifestation makes the world the
center of his radiance. His appearance
causes the world to attain to
maturity, and the extension of his
cycle is very great. Afterwards other
Manifestations will arise under his
shadow, who according to the needs of
the time will renew certain commandments
relating to material questions and
affairs, while remaining under his
shadow.
We are in the cycle which began with
Adam, and its universal Manifestation
is Bahá'u'lláh.
-- `Abdu'l-Bahá, Foundations
of World Unity, p. 54
The meaning of this is that any individual
who, before the expiry of a full
thousand years--years known and clearly
established by common usage and
requiring no interpretation-- should
lay claim to a Revelation direct from
God, even though he should reveal
certain signs, that man is assuredly false
and an impostor.
This is not a reference to the Universal
Manifestation, for it is clearly
set forth in the Holy Writings that
centuries, nay thousands of years, must
pass on to completion, before a Manifestation
like unto this Manifestation
shall appear again.
It is possible, however, that after
the completion of a full thousand years,
certain Holy Beings will be empowered
to deliver a Revelation: this,
however, will not be through a Universal
Manifestation. Wherefore every day
of the cycle of the Blessed Beauty
is in reality equal to one year, and
every year of it is equal to a thousand
years.
-- `Abdu'l-Bahá, Selections
from the Writings of Abdu'l-Baha, p. 67