Aṅguttara Nikāya
Ekakanipātapāḷi
Accharāsaṅghātavaggo
AN1.51
'This shining, almsmen, mind. OK and that stained from visiting stains that, not having learned, the commoner essentially does not know. From that not having learned I say 'cultivation of mind is not for the commoner'.'
AN1.52
'This shining, almsmen, mind. OK and that liberated from visiting stains that, having learned, the hearer of what is noble essentially does know. From that having learned I say 'cultivation of mind is for the hearer of what is noble '.'