p. 252
त्रिभिर्द्वाभ्यामेकतो वा विमुक्ताः क्रमाद्विशिष्टा मौनभूता भवन्ति ॥ २० ॥
In plain words
Grounded in three, two, or even one of these, they progressively attain excellence and become silent knowers of the truth.
Close to the Sanskrit
Liberated by three, two, or one, progressively distinguished, they become embodiments of silence.