Yoga sutra 2.12
kleśa-mūlaḥ karma-āśayaḥ dṛṣṭa-adṛṣṭa-janma-vedanīyaḥ
When mental afflictions form the basis of our behaviour, consciously or unconsciously, bad things result
Here Patanjali introduces the idea of karma. You cannot escape the consequences of your actions. Just as the wheel of a cart follows the hoof print of the animal that draws it, so suffering will surely follow when you speak or act from an impure heart. Also, as surely as your shadow never leaves you, so well-being will follow when you speak or act with a pure heart.
Damian Cadman-Jones is an authorised teacher of Prana Vashya Yoga™