諸經要集 3.78

3.78

Eighth, mindfulness of ānāpāna: this means one with concentrated diligence is mindful of ānāpāna. When the breath is long, one observes and knows: 'My breath is now long.' If the breath is short again, one should also observe and know: 'My breath is now short.' If the breath is extremely cold or extremely hot, one should also observe and know: 'My breath is now cold [or] hot.' Discerning the exhalations and inhalations, one counts the breaths as long or short. Eliminating all turbulent thoughts, one personally attains nirvāṇa. Not departing from ānāpāna, one then obtains merit. This is called mindfulness of ānāpāna.