Bhagavad Gita · 18.48

सहजं कर्म कौन्तेय सदोषमपि न त्यजेत्।सर्वारम्भा हि दोषेण धूमेनाग्निरिवावृताः॥

saha-jaṁ karma kaunteya sa-doṣham api na tyajet sarvārambhā hi doṣheṇa dhūmenāgnir ivāvṛitāḥ

O son of Kunti, one should not abandon one's natural duty, even if it has faults. All undertakings are covered by faults, as fire is covered by smoke.

— Bhagavad Gita 18.48

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)