Eastern mystics discovered that the whole existence is a materialized form of sound, of shabda. Hence we have said that the Vedas are the divine because they are shabda. And this has not only been discovered by the mystics of the East, but anyone who has searched in the dimension of being has found the same thing. The Bible says that in the beginning of creation there was the word, logos. From that sound, shabda, everything has been created.
Whosoever has searched for the foundation of life by entering into his own being has found “the sound” to be the most basic element of all. Those who have looked into the core of matter have found electricity to be the basic element. However, it is interesting to note that Western science says that sound is a form of electricity, and in the East Yoga says that electricity is a form of sound. Science and Yoga both agree on this point, that sound and electricity are not two different things. So it is only a matter of interpretation whether we call electricity a form of sound or we call sound a form of electricity. But science and Yoga both agree about one thing: that the smallest unit of life is either electricity or sound; there is no difference between them. They have both approached it from completely different directions and found the two forms of the very basic element of existence.
If you start looking into matter, in the end you will certainly stumble upon electricity. Matter is inanimate; electricity is also inanimate. If the search begins from consciousness then the basic elements of consciousness are found to be sound, words, thought, mind, reasoning. Howsoever deep we may go, the purer forms of sound will remain. And the ultimate form of sound we have called omkar, om.
This om is not confined only to the Hindus. The Jainas do not agree with the Hindus on the fundamentals of philosophy, but both agree on the fact that the sound of the ultimate inner happening is om. Buddhists do not agree with Hindus or Jainas on fundamental principles, but they do agree on the fact that when samadhi comes to its culmination, when enlightenment happens, the sound that is experienced within is om.
Mohammedans use the word ameen at the end of their prayer; Christians and Jews also use the word amen. Etymologists say that the word amen is just another form of om, because the inner sound may be understood by some as om and by others as amen. As far as sound is concerned, you can easily decode and interpret as you want. For example, when you listen to the sound of the wheels while traveling on a train, you can interpret them in any way you want. If you want you can hear them as the tune of a song, and someone who is a lover of movie songs will hear it that way. If someone is a devotee of Rama he will start hearing “Rama, Rama” in the sound of the wheels.
But the ultimate sound is very subtle. The mystics in the East have experienced it as om. Jewish and Mohammedan mystics have grasped it as “omen”, which later on became amen.