About 2500 years ago in India meditation was already a well-established spiritual practice. According to tradition, it was at that time that a young prince named Gautama resolved to find a way to end all the suffering in the world. After searching in vain for years, he decided to sit down and meditate until he found what he was looking for. After a long period of intense meditation, he gained great insight into his own being.
This event is called Awakening, or bodhi in the Sanskrit language, and Gautama became known as the Awakened One, or Buddha in Sanskrit. He spent the rest of his life living in accordance with that insight and teaching others about it. This started the Buddhist religion.
The Buddha taught that suffering was due to self-centred desires. To overcome this self-centredness, people should realise their true nature, and live in accordance with it. This includes realising that we are not separate from our surroundings, but that all things, including ourselves, intimately depend on each other and form an ever-changing seamless whole, with no divisions anywhere.
As Buddhism evolved, these concepts were elaborated in many different ways, to be more appropriate and helpful as teachings. One such development was the notion that all things are devoid of independent existence - this is sometimes called Voidness or Emptiness. Another way of expressing the nature of things was that they cannot be described and can only be experienced directly in their Suchness. Other teachers emphasised the seamlessly connected continuity of all things, likening them to a vast net, or to One Mind. Many of these ideas influenced Zen later.
While it is beneficial to receive such teachings intellectually, it is more beneficial to experience these things for oneself, rather than hear about them from other people. Meditation and other similar practices help us in this, and allow us to integrate our insight deeply into daily life.
In Sanskrit, meditation is called dhyana, and the stream of Indian Buddhism that emphasised meditation was called Dhyana Buddhism. As Buddhism spread through Asia, Dhyana was introduced to other countries. In China, it was called Ch'an, and was further developed and influenced by indigenous Chinese practices, such as Taoism. Later, it spread to Japan, where it was called Zen. Again, it evolved further, and in the 20th century, it was introduced into the Western world.
As a meditative tradition, Zen has produced teachings that are quite close to those of other similar streams in world religions, for example Sufism in Islam, or Christian Mysticism. In many cases, the differences are more a matter of relative emphasis, rather than fundamental disagreement.
Throughout the development of Zen, people have found that Awakening is not something that can be communicated in words. All the teachings of the many Zen teachers through history, and those of teachers from other traditions, can only point the way. We all have to make the journey for ourselves, and find new and appropriate ways of expressing our true nature day to day, minute to minute.