An age-old question leaving a trail of blood throughout the history of mankind.
The question also lies at the heart of the famous German play by Gotthold Ephraim Lessing: Nathan the Wise (1779). Nathan - himself Jewish - tries to bridge the gap between Judaism, Christianity and Islam. Then sultan Saladin asks him which religion is true?
In answer to this question Nathan tells the story of the magical heirloom ring handed down from God to mankind. Whoever wears the ring has the love of God.
At some point the ring ends up in the hands of a father who has three sons whom he loves equally. So, he promises the ring to each of them. Looking for a way to keep his promise, he has two replicas made, which are indistinguishable from the original, and on his deathbed he gives a ring to each of them.
The brothers quarrel over who owns the real ring. A wise judge admonishes them telling them it is impossible to tell, the original one supposedly having been lost at some point in the past. Yet this is a magical ring and in order to find out which of the sons has the real ring, it is up to them to live in such a way that their ring's powers are proven true.
In other words, the brothers should live a life that is pleasant in the eyes of God and mankind (rather than expecting the ring's miraculous powers to do the trick).
Gotthold Ephraim Lessing did not include Hinduism in Nathan the Wise. Not that it matters, for the ring parabel would still hold its ground. Religion is about God and God has many names and faces.
Judaism; seven divine names, such as: Yod-Hei-Vav-Hei, Elohim, El Shaddai and Adonai.
Christianity: Emmanual, Alpha, Carpenter, Everlasting Father
Islam; the 99 names of God, e.g. al Aziz, al Malik, al Gaffur, An Nur, Al Rashid.
All those divine names usually represent virtuous qualities. And believe it or not, Hinduism is not that different. Hindus, too, glorify and praise the thousands of qualities of the One God in his thousands of manifestations (avatars). Thus Lord Krishna, an avatar of Vishnu, symbolises Love. Lord Rama, another avatar of Vishnu, stands for Virtue. Hanuman is all about Power and the Goddess Saraswati represents Wisdom.The Bhagavad Geeta (Song of the Lord) has many verses that cleary mention the Oneness of God. The same book acknowledges others paths of worship, for instance through images of clay, stone copper, bronze, gold, silver, glass deities.
We bow. We worship. We do this in churches, temples, mosques, synagogues. We read holy scriptures. We rever Mary, Joseph, Jesus, Shiva, Vishnu, Laxmi, Shiva Linga, images of imam Ali, Husain, even the prophet Muhammad. And let us not forget what is inside the Kaaba: an ancient sacred black stone. Ring a bell?