The Patna Dharmapada 332

332

Uv2:10
anupūrveṇa medhāvī stokaṃ stokaṃ kṣaṇe kṣaṇe |
karmāro rajatasyaiva nirdhamen malam ātmanaḥ ||

Uv2:10
Gradually, bit by bit, at every moment, / the intelligent one should blow away his own impurity, just as a smith [blows away the dross] of silver.