This is often the first mantra taught to students, as it is melodic and simple but has within it practically the whole of yoga teaching. That is, a student is guided through the yoga meditation process simply by doing the mantra. As a student becomes more and more adept the mantra takes on resonance. By “adept”, I mean the student has been present for more and more teaching, they have hit up on and worked through some of the obstacles to their own practice, and have begun to have their own direct experiences and insights with the technique. Associations blossom. Other things fall away. The ‘meaning’ of the mantra becomes more personally potent and gilded with the process of one’s own journey.
It comes from several Yujur Veda Upanisads, like the Isha Upanishad. Soham means “I am He/She/That”. In Vedic teaching, it means identifying with the universal or ultimate reality. The mantra can be inverted to ham sa. Combining so’haṃ with haṃsa has been interpreted as “I myself am the Swan”. The swan symbolizes soul, or our true nature which is always pure, unbroken, unbreakable regardless of who we are, what we have done, or what has been done to us.
तेजो यत्ते रूपं कल्याणतमं तत्ते पश्यामि योऽसावसौ पुरुषः सोऽहमस्मि ॥१६॥
tejo yat te rūpaṃ kalyāṇatamaṃ tat te paśyāmi yo 'sāv [asau puruṣaḥ] so'ham asmi
"The light which is thy fairest form, I see it. I am what She/He is". Isha Upanishad, verse 16
Sometimes this is taught as the ‘prana’ or breath meditation, such that the inhale is sounded as ham and the exhale as so. We learn to take our minds from external to internal awareness, and eventually to an inner silence that is alive and humming. According to the Desickachar teaching of interiority, we first direct our mind to something. This protects and shelters the mind from wandering. The word mantra means protection for the mind. We allow this experience to change our state. And then we let go of the technique, the breath, the imagery and allow ourselves to be with the feeling as long as it lasts. We do not meditate for a set period of time or try to ‘empty the mind’. That generally involves fighting with ourselves and deepening our patterns. Instead, we allow a technique to bring us to a state, that state has some healing in it, and when it is done we move on.
As we focus on the sound, we are able to let the sound carry us ever deeper to a place of inner being.
An esoteric understanding of this mantra invokes the purity and grace of a swan, who is herself the embodiment of Saraswati. The swan represents a pure, wise mind. Apocryphally, the swan represents a trained mind because it can ‘separate’ milk from water. Swans do in fact have a capacity to filter mud from water, but the teaching here references the trained mind’s ability to take the milk (sweet, nurturing, nutritive, the nectar of amṛta) properties from something that is of mixed quality, like ordinary life. In other words, as we evolve on the yogic path, we are able to see the good, the opportunity, the beauty of human life and every passing circumstance. We can float.