In the Sudan, the Dinka and Nuer tribes have a bizarre tradition. "They extract the permanent front teeth of their children - as many as six bottom teeth and two top teeth - which produces a sunken chin, a collapsed lower lip, and speech impediments." 
Why? During a period of time in which lock jaw [tetanus] was common, children's jaws were slamming shut, preventing them from eating and drinking. The teeth are painfully removed with a fishhook. By pulling out up to eight permanent front teeth, the children could drink through the resulting hole that was left.
The tetanus epidemic has long passed, but the two tribes are still pulling adult teeth from their children's jaws, continuing a completely unnecessary pattern of injury.
The threat has long passed, yet the pattern continues.
Many Christians continue a similar pattern of self-injury, fearfully detesting their own heart and distaining the very core of their being. They unwittingly believe their heart continues to be the source of malice, sin and threat when it no longer is. Out of ignorance, many Christians wish they could extract the alleged evil within their hearts, not realizing that the epidemic sickness that once ravaged their hearts is no longer there.
In fact, the diseased heart was removed during conversion, when Jesus entered their bodies. Yet Christians continue a curious tradition of self-deprication and self-loathing - believing there is still a threat within them that makes them "prone to wander," selfish and opposed to God's will.
No longer in the heart, but in the body.
Though the Christian may and does still sin -- the source of that sin is no longer within their heart. Sin, as Paul indicates, may be lodged in the Christian's body...but not within her core nature [the heart]. "So don't allow sin to rule in your mortal body, to make you obey its desires." [Rom. 6:12]
In fact, you can count approximately 17 times throughout Romans chapters 6 through 8 the use of terms like, "flesh," "body," "members." This is why we "eagerly await our adoption, the redemption of our bodies."
The threat has passed.
That old, wayward heart [our core nature] was removed by Christ the moment you said 'yes' to Him. The threat of a former diseased heart is gone. Let's learn something from the Dinka and Nuer tribes, and stop a completely unnecessary and painful tradition based upon a diseased disposition that no longer exists. Your heart is good now. God made it so.
 "Mistakes Were Made - But Not By Me," by Tavris & Aronson