The works of Ādi Śaṅkarācārya

Sanatsujātīyam

p. 247

p. 247

कल्मषं तपसो ब्रूहि श्रुतं निष्कल्मषं तपः ।

In plain words

Tell me what stains austerity — I have heard that austerity is stainless.

Close to the Sanskrit

Tell the stain of austerity; austerity has been heard [to be] stainless.