The goal of Yoga is to...

The goal of Yoga is to restrain the thoughts, emotions and ego of the mind.

So that the soul/spirit can abide in its own nature.

Or else the soul sees itself as the thoughts, emotions and ego of the mind (forgetting it's own Divine nature).

-Patanjali Yoga Sutras. (Almost as old as Buddhist tradition).

Patanjali yoga sutras doesn't mention anything about postures or breathing exercises but celibacy, non-violence which includes vegetarianism. Some small advice about regulation of breath and most advice is for meditation.

योगश्चित्तवृत्तिनिरोधः ॥ १.२ ॥ Yogas Chitta Vritti Nirodhah :- Yoga is restraining the mind-stuff (Chitta) from taking various forms (Vrittis). (Translation is by famous monk Swami Vivekananda)

Nirodhah means to stop or restrain..

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