The tao is omnipresent. That means it is present throughout
Taoism, but that it is equally present throughout Islam,
Christianity, Judaism, Hinduism, Voodoo, Santeria, and every other
religion.
The tao is completely areligious. If being a part of the tao was a
religious experience or qualification, then every single person in
the world would be a Taoist. Tao and Taoism, however, are not the
same thing.
Taoism is a specific religious tradition and not everyone is a
Taoist. So while the tao may or may not require deities, that has
no bearing upon Taoism's requirement.
But how does Taoism require deities when the Dao De Jing doesn't
seem to mention them?
In order to understand that, one has to first examine Taoism's
historical development.
The Dao De Jing dates to the 6th - 2nd Centuries B.C. Taoism was
established as a formal religion in the 2nd Century A.D. No matter
where one places the Dao De Jing, it came into existence at least
several centuries prior to Taoism's founding.
By the time Taoism came into existence, it relied upon a complex
foundation of ideas and traditions, of which Laozi's philosophy was
only a part. This foundation came to be captured within a "canon"
or an officially sanctioned group of core religious texts.
The earliest versions of the canon contained many thousands of
texts, of which the Dao De Jing was but one. The fact that one text
within the canon may not contain a specific idea does not mean that
the rest of Taoism does not hold that same idea to be valuable and
necessary.
It is also questionable whether anyone can make a concrete case
that the Dao De Jing doesn't consider deities.
There are several passages in the Dao De Jing that seem to imply
recognition of deities. But even more important is the fact that
Taoists often interpret the Dao De Jing in radically different
manners than do standard Western translators.
Whereas Americans simply walk into a bookstore and purchase a copy
of a translation, Taoists are traditionally taught an oral
tradition of interpretation that has great religious and ritual
importance. Taoists see deities in the Dao De Jing, while
areligious Western translators often do not.
Taoism, from its very beginnings until today, incorporates deities.
It doesn't, however, recognize a God in the Western sense. There is
no great omnipotent being, external to man, who manages the
universe. Such management is left to the tao, but the tao itself is
not worshipped. Taoist deities are part of our universe, not
separate from it, and are as equally beholden to the movements of
the tao as are normal people. In that sense they are "deities"
moreso than "Gods."
They are worshipped or venerated in Taoist temples. Without
deities, there would be no need for temples! Taoist deities exist
in a great pantheon. Within this pantheon is a structure, with
various deities operating under the authority of other
deities.
The pantheon generally changes over time, and various Taoist sects
have differing views of it. But all Taoist sects acknowledge the
pantheon's existence.
