Bhagavad Gita · 9.31

क्षिप्रं भवति धर्मात्मा शश्वच्छान्तिं निगच्छति।कौन्तेय प्रतिजानीहि न मे भक्तः प्रणश्यति॥

kṣhipraṁ bhavati dharmātmā śhaśhvach-chhāntiṁ nigachchhati kaunteya pratijānīhi na me bhaktaḥ praṇaśhyati

Quickly such a person becomes righteous and attains lasting peace. O son of Kunti, declare boldly that My devotee never perishes.

— Bhagavad Gita 9.31

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