Mark 7:18-23
And he saith unto them, Are ye so without understanding also? Do ye not perceive, that whatsoever thing from without entereth into the man, it cannot defile him; Because it entereth not into his heart, but into the belly, and goeth out into the draught, purging all meats?  And he said, That which cometh out of the man, that defileth the man.  For from within, out of the heart of men, proceed evil thoughts, adulteries, fornications, murders, Thefts, covetousness, wickedness, deceit, lasciviousness, an evil eye, blasphemy, pride, foolishness: All these evil things come from within, and defile the man.

There is nothing that can enter into us and defile our hearts, corrupt us, or make us evil.  That is already within our hearts, because sin is a built-in problem.  We already have the potential within us to do the worst kinds of things.  So we tend to rebel against what is right and good.  We give in to that part of us that does whatever it wants to do.  All of these things Jesus mentions come forth from within us and make us dirty down to the deepest parts of our souls.

One of the biggest mistakes we make as humans is that we often consider ourselves inherently good.  This plays out in different ways, whether it’s that we consider ourselves “good” as long as we don’t do “really bad” things or whether we think if we just do enough “good” things, we’ll be okay.  But that is a skewed perspective of humanity that only sets us up for further trouble down the line.  We may try all kinds of things to make ourselves feel clean, but all of our efforts will be in vain.

The truth is that no amount of cleansing can reach deep enough.  Water and soap cannot go down into our hearts and wash away the stains of sin.  Cleaning up the outside doesn’t touch the part of us that needs cleansed the most.  It is more than trying to feel clean or seem clean by doing the traditional cleansings like the Pharisees were doing.  That is why God Himself intervenes, because it takes something outside of us.  He offers us the opportunity to be cleansed from the inside out.  The blood of Jesus washes away our sin, and then we have His Spirit within that tempers our evil and enables His good.

It is an unpleasant thing to walk around with dirty hands or to eat with unwashed hands, but even worse is to walk around with a dirty, corrupted, sin-marred heart.  But Jesus can set us free from all the evil that defiles us.  He can make us wholly clean and keep us that way.  He can cleanse any stain, forgive any sin, redeem any mistake, and change our hearts into a fertile field that will truly produce good and righteous fruit from our lives.