Nakulapitusutta

sn22.1:11.1 They regard perception as self, self as having perception, perception in self, or self in perception.

sn22.1:11.2 They’re obsessed with the thought: ‘I am perception, perception is mine!’

sn22.1:11.3 But that perception of theirs decays and perishes,

sn22.1:11.4 which gives rise to sorrow, lamentation, pain, sadness, and distress.