Let's say you have a cup of coffee, but don't drink all of it and put it in the sink. You don't wash it out; it just sits there. The coffee will get stronger and more bitter the longer it sits. If you let it sit for a long time, mold will even grow on it.
However, if you immediately pour water into it, the coffee gets lighter and lighter until there is no coffee left, but only water in the cup. There is not even a ring in the cup showing where the coffee once was.
If we let sin stay in our "cup" of life, it gets stagnant, bitter and grows as we get more desensitized to it. Our "little" sins (by the way, there are no "little" sins) become big ones as our hearts grow more hardened to the Lord's still, quiet voice, and "mold" starts to grow in our hearts. Things that once pricked our conscience and convicted us no longer phase us. Even the smallest amount of unforgiveness can turn ugly.
However, if we fill our "cup" with the Word, with prayer, seek God and fellowship with other believers, God starts taking the...