योगः कल्पतरुः श्रेष्ठो योगश्चिन्तामणिः परः ।
योगः प्रधानं धर्माणां योगः सिद्धे स्वयंग्रहः ।।
– आचार्य-हरिभद्रसूरेः योगबिन्दुः
(yogaḥ kalpataruḥ śreṣṭho yogaścintāmaṇiḥ paraḥ ।
yogaḥ pradhānaṃ dharmāṇāṃ yogaḥ siddhe svayaṃgrahaḥ ।।)
– Yogabindu of Haribhadrasūri
Yoga is a kin to the type of the tree namely kalpa, yoga is akin to the best type of jewel namely cintāmaṇi yoga is chief among the virtuous performances, yoga is the very attainment of supreme success (i.e. mokṣa).
[The tree namely kalpa (kalpataru) and the cintāmaṇi jewel are mythological entities which fulfill all desires whatsoever of those who have access to them.]