[136] And what, Rāhula, is the water element (āpodhātu)? The water element may be internal or it may be external. And what, Rāhula, is the internal water element? Whatever internally, belonging to oneself, is water, watery, and clung-to (upādinna), namely: bile, phlegm, pus, blood, sweat, fat, tears, grease, saliva, snot, synovial fluid, urine — or whatever else internally, belonging to oneself, is water, watery, and clung-to: this, Rāhula, is called the internal water element. Now both the internal water element and the external water element are simply the water element. That should be seen as it really is with right wisdom thus: 'This is not mine, this I am not, this is not my self.' Having seen it thus as it really is with right wisdom, one becomes disenchanted with the water element; one detaches the mind from the water element.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.