The article is…slightly biased…
Three primary religions are considered monotheistic—maintaining belief in one supreme Creator: Christianity, Islam and Judaism. All three revere Jerusalem as a holy city. None agrees fully on the way to worship the one God they all espouse.
Logic demands that if there indeed is one God, then it ought to follow that He would define the proper manner in which to worship Him, and reveal that way to man. Yet these religions differ vastly in doctrine and in practice.
One of these, Judaism, claims that the Old Testament writings preserved from ancient times by the Jews are the revealed instructions to man on how to worship God.
Varying divisions of Christianity lay claim to the same book, the Bible—incorporating both the Old Testament preserved by the Jews (albeit in differing versions) and the New Testament preserved by the Greeks—as the basis of their religion. Yet they disagree on their interpretation of its teachings.
The third of these great religions places faith in another book as the Creator’s revealed knowledge of how to worship and obey God: the Koran of the Islamic faith.
Within each of these religions are many diverse branches, differing on religious beliefs and practices to the point of confusion as to just what it is that represents core doctrine. If religion is, indeed, the opiate of the masses, as Marx declared, then among these religions there is a brand to suit all tastes.
Is there one true faith? If not, then based on the assumption of all three of these religions that there exists one supreme God over all, has that God destined mankind to a life of confusion over the very basic questions about His nature, His religion and the reason He created man? These are fundamental questions with which countless generations of thinkers, philosophers, religionists and educationalists have wrestled for 6,000 years of documented human history.