Yoga Sutras of Patanjali translated by Yogi Kalinath - Chapter 3, Verse 6
Pada 3, Sutra 6
Tasya bhoomisu viniyogah
Its (Samyama’s) application / progression is in stages.
The application of Samyama just like Yoga itself is a gradual process leading to Prajna or Illuminous Insight of not only objects of attention themselves but of the very nature of existence, the Self.
For realization of the True Nature of things (i.e. Revelation of Essence and Universal Truth) and its integration in conscious awareness, a firm foundation must be erected stage by stage.