When encountering Hinduism for the first time, Westerners (including many of the students in my community college Eastern religions classes) find themselves faced with a major world faith which in many ways differs drastically from the major Western faiths with which most of them are familiar.
For another thing, Hinduism also believes that individuals spend not just one lifetime upon this earth, but many.
For still another thing, Hinduism believes in both polytheism and monotheism. Simultaneously.
Okay, hold on. The popular Hindu pantheon is comprised of Vishnu, Shiva, Brahma, Ganesha (the famous elephant-headed son of Shiva), Hanuman (the monkey god), Kali, Durga, and countless other deities. One traditional formulation states that there are in fact some 330 million gods. How can an assertion like that ever logically square with monotheism, or the belief in just one God?
Hinduism believes in (and worships) multiple gods. Yet behind or above or beyond that superficial multiplicity also lies a deeper unifying and singular divine Reality. In other words, Hinduism is both monotheistic (in theory) as well as polytheistic (in practice).
In a way which many Westerners find it difficult to wrap their minds around, Hinduism believes that there is more than one valid way of conceiving or conceptualizing of God or the Divine. And more than one of these ways may be “in play” at one time, even within the faith life of a single individual.
In other words, Hinduism simultaneously employs multiple “versions” or “public images” of God. Hindus revere a pantheon of multiple gods, yet ultimately affirm a single Supreme Reality.
Many Hindus conceptualize and worship God primarily in the guise of Vishnu. Other Hindus instead visualize and worship God primarily in the form of Shiva. Still other Hindus resonate more with worshipping God explicitly as Devi or Goddess (in any of a number of variant feminine manifestations — as Kali, as Durga, etc.). Yet other Hindus conceive of God or the Divine in nonpersonal or transpersonal terms, e.g., as Brahman, the impersonal Absolute, the Ground of Being, the Supreme Reality, or All That Is.
Many Hindus may worship any or all of these deities (or alternate forms of Deity), together also with any of a number of avatars or earthly “incarnations” of Deity (as Krishna, for instance, or as Rama) simultaneously, and without any sense of inconsistency or self-contradiction. They do so by understanding all of these many deities as being just so many variant forms, facets, aspects, masks, personae, or manifestations of the same single Supreme Being.
From the Hindu perspective, other (non-Hindu) religions merely extend this diverse variety of ways of conceptualizing and approaching God or the Divine. Consequently, in the Hindu view, all religions are equally valid, insofar as each in its own way serves as just another alternate route leading up the same Mountain; all such valid spiritual paths ultimately converge upon the same Goal.
As the Hindu Vedas put it so succinctly, “Truth is One; sages call it different names.”