Verse 20

इदं कृत्वेदमप्यन्यत्कर्तव्यमिति कल्पनाम् ।कदान्तर्विहसिष्यामि पदविश्रान्तया धिया

In plain words

When, with a mind come to rest in that state, shall I laugh within at this very notion — 'having done this, yet another thing remains to be done'?