Buddhist Dictionary of Pali Proper Names by G P Malalasekera
Sūka Sutta
Sūka Sutta:If a spike bearded wheat or barley be badly grasped by hand or foot,it does not pierce hand or foot; but it will if firmly grasped.Similarly a mind which is ill directed will not pierce ignorance or draw knowledge; but it will if well directed.A.i.8f.