Verse 18

ममेदमित्यसद्भूतमिन्द्रियार्थे भवन्मनः ।मा निमज्जत्वमग्नः सन्मा करोतु करोतु वा

In plain words

Let not your mind sink into the object of sense with the unreal notion 'this is mine'; remaining unsubmerged, let it not act, or let it act.