Mudutavagga

Suttapiṭaka · Saṁyuttanikāya · Mahāvaggasaṁyutta · Vol. 19 · Section 873

[873] And what, bhikkhus, is the faculty of mindfulness (satindriya)? That mindfulness, bhikkhus, which one obtains in dependence on the four establishments of mindfulness (satipaṭṭhāna) — this, bhikkhus, is called the faculty of mindfulness.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

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