The heart is deceptive and beyond cure, so says the prophet Jeremiah. Sounds like someone who has been burned, but it is a word of wisdom. Our hearts tell us things that our heads know are not wise or just plain wrong. But emotions can sway even the most disciplined and rational person.
Proverbs 28:26 says, "He who trusts in his own heart is a fool, but he who walks wisely will be delivered."
Implied in this is a trust in the Lord that springs from a holy fear of God. It is a lifestyle that keeps one from a multitude of sorrows and regret.