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how might contemporary psychology's understanding of self deception relate to these ancient texts?

Adds the setting and its conversation across both testaments.

Jeremiah 17:9

“The heart is deceitful above all things, and it is exceedingly corrupt: who can know it?”

This verse comes from the prophet Jeremiah, who was speaking to the people of Judah in the late 7th and early 6th centuries BCE. He was calling them to repentance as their society faced political collapse and moral decay, warning them of impending judgment from Babylon.

How might acknowledging our capacity for self-deception encourage a more honest approach to our inner lives and outward actions?

Then — the setting

Jeremiah prophesied during a turbulent period, roughly 627-586 BCE, before and during the Babylonian exile. He addressed a Judean society that had largely abandoned the covenant with God, engaging in idolatry and social injustice. His message highlighted a deep-seated spiritual and moral corruption that extended beyond outward actions to the very core of human inclination, which he termed 'the heart.' This wasn't merely a personal failing but a societal condition, suggesting a collective self-deception about their spiritual health despite outward religious practices.

Across the Testaments

The Old Testament, particularly the wisdom literature (Proverbs, Ecclesiastes) and prophetic books, frequently explores the 'heart' as the seat of intellect, will, and emotion, often warning of its susceptibility to evil and pride (e.g., Proverbs 16:5). Jeremiah's stark assessment in 17:9 underscores the pervasive nature of sin and the difficulty of self-knowledge. The New Testament affirms this ancient understanding, with Jesus teaching that evil thoughts and actions originate from the heart (Mark 7:21-23). Paul, in Romans, describes an internal struggle where the 'flesh' (often paralleled with the 'deceitful heart') wars against the spirit, acknowledging the human propensity to act against one's known good (Romans 7:14-20). Both testaments concur that true change requires divine intervention to transform the heart.

Keep thinking

Read alongside it

Proverbs 28:26
Warns against trusting one's own heart, emphasizing the need for wisdom.
Romans 7:15
Paul describes an inner conflict, doing what he doesn't want, illustrating human struggle with self-knowledge.
1 John 1:8
States that if we claim to be without sin, we deceive ourselves.

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