[856] The Blessed One said this: "And how, Ānanda, is there the unsurpassed development of the faculties (indriyabhāvanā) in the discipline of the Noble One? Here, Ānanda, when a bhikkhu has seen a form with the eye, there arises what is agreeable, there arises what is disagreeable, there arises what is both agreeable and disagreeable. He understands thus: 'There has arisen in me this agreeable, there has arisen this disagreeable, there has arisen this both agreeable and disagreeable. But that is conditioned, gross, dependently arisen; this is peaceful, this is sublime — namely, equanimity.' In him that arisen agreeable, that arisen disagreeable, that arisen both agreeable and disagreeable ceases, and equanimity becomes established. Just as, Ānanda, a man with good eyes, having opened them, might close them, or having closed them, might open them — even so, Ānanda, for whomsoever, thus swiftly, thus quickly, thus without difficulty, the arisen agreeable, the arisen disagreeable, the arisen both agreeable and disagreeable ceases and equanimity becomes established — this, Ānanda, is called, in the discipline of the Noble One, the unsurpassed development of the faculties with regard to forms cognizable by the eye."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.