Translated from Taishō Tripiṭaka volume 2, number 99
Thus have I heard. At one time, the Buddha was abiding in Śrāvastī, in the Jeta Grove, in Anāthapiṇḍada’s Park.
At that time, the Bhagavān said to the bhikṣus, “If a bhikṣu cultivates ānāpānasmṛti, so that it is cultivated much, he obtains great fruit, and great benefit. What is cultivating ānāpānasmṛti, so that it is cultivated much, obtaining great fruit and great benefit? This bhikṣu, with a mind fully engaged in ānāpānasmṛti, cultivates the Bodhi factor of Mindfulness, in accordance with detachment, in accordance with desirelessness, in accordance with cessation, tending toward abandonment... even up to cultivating the Bodhi factor of Abandoning, in accordance with detachment, in accordance with desirelessness, in accordance with cessation, tending toward abandonment.”
After the Buddha had spoken this sūtra, the bhikṣus heard what the Buddha had said, and joyfully practiced in accordance.