Dutiyaarahantasutta

sn22.77:1.1 At Sāvatthī.

sn22.77:1.2 “Mendicants, form is impermanent.

sn22.77:1.3 What’s impermanent is suffering.

sn22.77:1.4 What’s suffering is not-self.

sn22.77:1.5 And what’s not-self should be truly seen with right understanding like this: ‘This is not mine, I am not this, this is not my self.’