What does the Bible say about deceit?

Proverbs 20:17 states that the bread of deceit is sweet to a man, but later his mouth is filled with gravel. This illustrates the deceptive allure of lies, particularly in spiritual matters, where false teachings can appear satisfying but lead to eternal consequences. It emphasizes that those who embrace deceit do so because they love lies, prioritizing the temporary pleasures of the world over the truth found in Christ. The contrast of sweet deceit versus the ultimate bitterness of gravel reflects the nature of spiritual nourishment that does not fulfill the soul's true hunger for God.