When the posture is steady, the body is still and comfortable, and you are breathing diaphragmatically, the next step is breath awareness—observing the flow of your breath.
Let your mind be focused on the breath and allow the mind to flow with the breath. The breath should not be jerky or shallow, it should not be noisy, and you should not uselessly expand the natural pause between inhalation and exhalation.
Breath is a barometer to measure one’s inner state. When you observe that your breath is serene, deep, and without any unnecessary pause, you will experience a sense of great comfort and joy.
The more the mind is made steady and one-pointed, the more one experiences peace and happiness. There are several ways of making the mind steady and one-pointed. Among them, concentration on inhalation and exhalation is considered to be the best.
Concentration on the flow of breath is one of the best ways to attain control over the modifications of the mind. When all the modifications cease, and the mind is calm and tranquil, one finds great joy within. When the mind is free from all distractions, and starts traveling inward, an aspirant begins to unveil the mystery of multilevel reality. Through a one-pointed mind, one gains knowledge of the inner world. This knowledge is superior to that derived from perception, inference, or testimony.
You will find extraordinary joy when you have coordinated the mind with the breath. Gradually you move your mind from the breath to sound awareness. The sound "so-hum" is the best to concentrate upon. When you remember "so-hum," "so" is the sound of inhalation and "hum" is the sound of exhalation.
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With your eyes closed, focus your mind on the lowest center along the spinal column, called muladhara. Inhale as though you are inhaling from the root of the spinal column, while inhaling the sound "so;" then exhale with the sound "hum," as though you are exhaling from the crown of your head to your toes.
In this way the ratio of exhalation to inhalation will be double—inhale four and exhale eight. Do it ten times after practicing diaphragmatic breathing. After a few days, you will find your breath has become very calm.
Whenever you are in great joy, you will find that the mind is calm and the breath is serene. You can never remain in joy and you can never be happy, unless there is perfect coordination between the breath and mind.
Life is breath and breath is life.
You often close your eyes and sit down and you don’t know what to do next; then you start remembering your mantra. You can remember your mantra all the time, but that’s not very systematic. It will take a long time for you. You’re doing japa, but you’re doing it halfheartedly. If you do the same thing with full concentration, it will definitely give you results.
When you remember your mantra, you should remember it with all your feeling. You should know about your mantra—understand what your mantra is.
Remember your mantra as silently as possible, and it will help you tremendously. Let your mind be led by your mantra and let it become a part of your life.
Remember your mantra—slowly, gently—and follow it. The sound will take you to the soundless state that is beyond body, breath, and mind. That is what meditation is.
From The Essence of Spiritual Life
By Swami Rama
Source : https://www.swamij.com/swami-rama-breath-sohum.htm