Chapter 5 · The Yoga of Renunciation · Krishna said
Bhagavad Gita 5.15 — Ignorance causes delusion
नादत्ते कस्यचित्पापं न चैव सुकृतं विभुः। अज्ञानेनावृतं ज्ञानं तेन मुह्यन्ति जन्तवः ॥
nādatte kasyacitpāpaṃ na caiva sukṛtaṃ vibhuḥ | ajñānenāvṛtaṃ jñānaṃ tena muhyanti jantavaḥ ||
Meaning
The all-pervading Lord takes on no one's sin or good deed. Knowledge is covered by ignorance, and that is why beings are deluded.