This question was tantamount in my search for the truth of mankind's existence. Since I had worshipped in at least three somewhat competing protestant churches by the time the decade of the 1980's had arrived, I knew that no one, in fact, must possess the ultimate truth, but like all truth, small bits of it were strewn throughout the religious dogmas and doctrines of mankind. Upon the termination of viewing a PBS documentary about the history behind biblical stories, I found that connecting threads of truth, the early version of it anyway, started to unravel pretty early in history. As competing and warring sects of one religion would break away, and as one dynastic world power subjugated another, religious truths morphed and multiplied, and it is very easy to spot, from a historical perspective, that these truths, far from being "self-evident", have been reinterpreted and reinvented throughout history.
My prophecy is simple. All truth is subjective to the truth teller. He believes. He worships. He knows. Or at least he knows irrespective of listening to any and all of the truths competing for airspace with his. My philosophy would have to connect the dots of the competition, and find the truth through the lies. All of recorded religious history cannot be wrong. What if it were right most of the time? What if there are many "prophets", all operating under the assumpition that they are really hearing the voice of God int their heads. God talks in many languages, and often at the same time. Is it any wonder that most of mankind has had a little trouble trying to make sense of what he says.
In the Pentecostal faith, "speaking in tongues" is not only believed, but encouraged, or at least it was when I attended services. One who is not completely immersed in the culture of that particular experience, might even scoff or laugh at the seeming ridiculousness of the proceedings.
I could, and do, embrace the many pleading questions Mankind has asked throughout his existence.
Since he has many voices, and only one set of ears, Mankind pretty much has listened only to what he believes anyway.
Hence the different Gods, the different Faiths, and the different ways of expressing it.
I listen to voice of the Universal Mind, which speaks silently in the language of The Ultimate Truth. It coaxed me to waive my belief in an "established system of belief", no matter how steeped in tradition and history it would seem. I strive to find the similarities in Mankind's search for Truth, and start from there. There is a higher power, and it is a power we all possess. Faith is not a covenant, but a realization. Why can't our beliefs seek to find the similarities? That is the Universal Goal.