Yoga Sūtra Chapter Three verse 4
त्रयमेकत्र संयमः ॥४॥
trayam-ekatra saṃyamaḥ ||4||
The three in the same place is complete restraint.
traya - the threeekatra - in the same placesaṃyama - complete restraintCommentaries and Reflections
Commentary by T Krishnamacharya:
The evolution of Samādhi is Sthūla Savitarkā to Sthūla Nirvitarkā.
This is Viniyoga Krama, then Sūkṣma Savicārā to Sūkṣma Nirvicārā.
Commentary to Yoga Sūtra Chapter Three verse 4
Cross referencing to Yoga Sūtra Chapter One verse 42-44.