When all the Pandavas became experts in arms and sure in aim, then Drona thus spoke demanding his preceptorial fee.
यदा च पाण्डवाः सर्वे कृतास्त्राः कृतनिश्चयाः। ततो द्रोणोऽब्रवीद् भूयो वेतनार्थमिदं वचः॥