Mahārāhulovādasutta

mn62:12.1 And what is the space element?

mn62:12.2 The space element may be interior or exterior.

mn62:12.3 And what is the interior space element?

mn62:12.4 Anything internal, personal, that’s space, spacious, and appropriated. This includes:

mn62:12.5 the ear canals, nostrils, and mouth; and the space for swallowing what is eaten and drunk, the space where it stays, and the space for excreting it from the nether regions; or anything else internal, personal, that’s space, spacious, and appropriated.

mn62:12.6 This is called the interior space element.

mn62:12.7 The interior space element and the exterior space element are just the space element.

mn62:12.8 This should be truly seen with right understanding like this: ‘This is not mine, I am not this, this is not my self.’

mn62:12.9 When you truly see with right understanding, you grow disillusioned with the space element, detaching the mind from the space element.