Majjhima Nikaya 3:71
SUJATO‘vimocayaṁ cittaṁ assasissāmī’ti sikkhati, ‘vimocayaṁ cittaṁ passasissāmī’ti sikkhati.
They practice like this: ‘I’ll breathe in freeing the mind.’ They practice like this: ‘I’ll breathe out freeing the mind.’
‘vimocayaṁ cittaṁ assasissāmī’ti sikkhati, ‘vimocayaṁ cittaṁ passasissāmī’ti sikkhati.
They practice like this: ‘I’ll breathe in freeing the mind.’ They practice like this: ‘I’ll breathe out freeing the mind.’