Ajjhattadukkhahetusutta - translated by Bhikkhu Bodhi
“Bhikkhus, the eye is suffering. The cause and condition for the arising of the eye is also suffering. As the eye has originated from what is suffering, how could it be happiness?
“The ear is suffering…. The mind is suffering. The cause and condition for the arising of the mind is also suffering. As the mind has originated from what is suffering, how could it be happiness?
“Seeing thus … He understands: ‘… there is no more for this state of being.’”