If you break the chant down, there are also three syllables, A. U. M., representing the Trinity of God in Hindu dharma (Brahma, Vishnu and Shiva).
The A sound represents the beginning, the birth, the start of creation and the start of everything. Brahma.
The U sound represents the Diving energy. It stands for preservation. Vishnu.
The M sound represents destruction. Shiva.
The three letters also refer to the three planes of existence: heaven, earth, and the underworld.
In yoga, we honor the trinity by chanting Om three times. When you say om, the three syllables flow effortlessly into the next, just like your inhale flows to your exhale and into your next inhale. It’s a slow, focused movement of all things forward.
So, why do we chant this at the beginning and end of class? Because om is the mother of all mantras that unites us with the Divine. It connects our mind to our body to our soul; it connects us to all the movement in the universe and to all of humanity. Uttering the very sound of creation allows us to tap into that divine energy. Om leads our mind into a deep concentration, and then transitions it to meditation, then into Samadhi (a state of higher consciousness).
Om is a chant that opens up the entire universe to you and at the same time offers all the stillness and focus in the universe as you tune into the holy vibration of all things.