One verse

Srimad Bhagavatam 6.1.18

6.1.18

प्रायश्चित्तानि चीर्णानि नारायणपराङ्‍मुखम् । न निष्पुनन्ति राजेन्द्र सुराकुम्भमिवापगा: ॥ १८ ॥

prayascittani cirnani narayana-paranmukham na nispunanti rajendra sura-kumbham ivapagah

prayascittani
processes of atonement
cirnani
very nicely performed
narayana-paranmukham
a nondevotee
na nispunanti
cannot purify
rajendra
O King
sura-kumbham
a pot containing liquor
iva
like
apa-gah
the waters of the rivers.

My dear King, as a pot containing liquor cannot be purified even if washed in the waters of many rivers, nondevotees cannot be purified by processes of atonement even if they perform them very well.