Verse 19

रूपं कच्चिदविद्याया बलाद्भङ्गुरमाततम् ।अनन्तमन्तवच्चैव सम्यक्स्मरसि सन्मते

In plain words

Do you rightly remember, O one of true understanding, the form of avidyā -- fragile, yet spread wide by force; without end, and yet also having an end?