In this videoconference talk from 5 June 2020, Ajahn Anan discusses peace and the mind that is unaffected by sense objects, like clear water.

"The mind is luminous by nature. But we can see that when the mind gets involved with sense-objects, then the mind changes its quality."

Note: One can read this talk and others at the Wat Marp Jan 'Reflections' page, which also includes questions and answers with Ajahn Anan, which are not in the audio files. See: https://watmarpjan.org/en/dhamma-reflections/reflections-archive/