Biblically, the heart is the source of a person's behaviors, beliefs, thoughts, attitudes, desires, motives, and values. The heart is so important to who we are: our inner nature that is given a new body for our eternity in Jesus. God made the heart naturally stable by making it greatly fear getting changed. This is good, but also causes the heart to be very self-deceptive. If it needs to be cleaned, how can we proceed? This book shows the Biblical picture of the heart more fully, so that we can see ways for believers in Jesus to work with Him to clean our deceiving hearts for our eternity and for our close life-giving fellowship with God on earth. I gave two related books the same cover, so that readers can choose the best fit. Purifying the Heart puts solutions of heart-problems with their discussion: this complicates the picture of the heart. Destroying Spiritual Strongholds more fully explains this picture from the Bible, which is a harder introduction to this picture.