While society has been teaching us for a number of years that our 'self-esteem' is of the utmost importance God's Word teaches quite the opposite.
The ubiquitous pseudo psycho-babblers all around us are leading thousands of people in the wrong direction, away from what the Bible so clearly teaches. Rather than a positive self-image, what we need is a realistic self-image. We need to see ourselves as God sees us. Paul warned: "For I say, through the grace given unto me, to every man that is among you, not to think of himself more highly than he ought to think; but to think soberly, according as God hath dealt to every man the measure of faith" (Romans 12:3).
Even though we think highly of Paul, he esteemed himself as "chief of sinners" (1 Timothy 1:15), even after being one of the most important leaders of the early church for many years.
True humility cannot be purchased. It is the result of seeing ourselves in the true light of God's Word - as sinners saved by grace.