Scripture warns that deception is a serious sin, coming from the human heart and from external sources like false teachers and the devil. Key verses include Jeremiah 17:9, which states that "the heart is deceitful above all things," and Ephesians 5:6, which advises against being "deceived with empty words". Overcoming deception involves rejecting lies, practicing truthfulness, and discerning false teachings by comparing them to the Bible.