। ॥
In plain words
You must not think: 'With a mind purified by performing required duties and freed from prohibited and selfish actions, one awakens to his own true awareness. What need is there for a teacher?'
Close to the Sanskrit
'Free of both kāmya and niṣiddha actions, with a pure mind through the performance of prescribed duties, one attains his own very awareness—what need is there for the guru?' This must not be thought by you.