Proverbs 20:9 Kabbalah

מִֽי־יֹ֭אמַר זִכִּ֣יתִי לִבִּ֑י טָ֝הַ֗רְתִּי מֵחַטָּאתִֽי׃

Who can say: ‘I have made my heart clean, I am pure from my sin’?

Read kabbalistic (mystical) interpretation of Proverbs 20:9: and classical mystical sources.