From this Saturday when I begin running a 6-week course on Patanjali’s Yoga Sutra, I will be very much a beginning yoga teacher again.
The Sutra are a topic which I’ve never taught before so I am fraught with doubts about my ability to give the students the true value of the Old Sage’s teaching. Will I be coherent? Will I have enough of a grasp to convey salient points? Will I be able to make the subject interesting enough?
I decided that I would only feature some of the Sutra in this course, the ones that I’ve found useful and that have become part of the fabric of the way I teach. This seems like an honest approach, and it’s the way I teach my asana classes – from my bones.
Today’s Sutra is an example of one that at this time I find way over my head. But nevertheless, I grapple with it because that’s what I did years ago with those Sutra which I eventually learned to comprehend – mainly those of Chapters I and II.
An old Patanjali scholar, Shyam Ghosh, explains Sutra IV-23 like this:

The mind is like a mirror: it reflects whatever is close to it [either the Self or objects]…. However, reflection in the mirror is clear only when the mirror is perfectly clean…. When the purity of the Self is fully and truly reflected in the mind, the two merge and become one.*

*The Original Yoga – as expounded in Siva-Samhita, Gheranda-Samhita and Patanjala Yoga Sutra.

Drastrdrsyoparaktam cittam sarvrtham

Thus the mind serves a dual purpose. It serves the Perceiver by presenting the external to it. It also reflects the Perceiver to itself for its own enlightenment.**
**Patanjali’s Yogasutras, translation and commentary by T.K.V. Desikachar.