A MAN, very much annoyed with a Flea, caught him at last, and said, "Who are you who dare to feed on my limbs, and to cost me so much trouble in catching you?' The Flea replied, "O my dear sir, pray spare my life, and destroy me not, for I cannot possibly do you much harm." The Man, laughing, replied, "Now you shall certainly die by mine own hands, for no evil, whether it be small or large, ought to be tolerated."  (From Aesop’s Fables)

Oh, that more believers would heed this lesson: “no evil, whether it be small or large, ought to be tolerated.”  Since reading The Mortification of Sin, the words of John Owen have stuck with me,

“Sin aims always at the utmost: every time it rises up to tempt or entice, might it have its own course, it would go out to the utmost sin of that kind…And so far as the soul is made insensible to any sin, that is, as to such a sense as the gospel requires, so far it is hardened.  But sin still pressing forward; and that because it hath no bounds but utter relinquishment of God, and opposition to him.”  (From, The Mortification of Sin)

If you let a couple of fleas go in your house before you know it your entire house will be infested with fleas.  My wife and I, unfortunately, know this all too well.  Our cat ended up not only getting pregnant but also getting fleas.  Because she was pregnant we felt it best to try to quarantine her in a room and deal with the fleas later.  That was dumb.  Now we are going to have buy flea stuff for the cat and her kitties as well as tons of flea killer for our house.  We should have tried to kill the fleas before this became a problem.

Sin does this exact same thing in our lives.  “It is only a little sin,” we rationalize.  Friend, there is no such thing as a little sin.  Every sin if given opportunity will harden your heart, lead to forsaking the gospel, and relinquishing God from his throne.  Even it its seminal stages sin is an affront to God and his glory, and ought to be dealt with.   

One area that I have seen this most frequently is in the area of teenagers involved in inappropriate relationships.  We have lost numerous students, once seemingly passionate about Jesus, to boyfriends or girlfriends.  Ultimately, I know that if these students are in Christ that he will doggedly pursue them and work repentance in their heart.  Nonetheless, the pain that is caused by this is jarring. 

It starts with an “innocent” relationship.  Then mistakes are made.  Then it gets uncomfortable being around God’s Word and God’s people.  At the crossroads the student will either end the relationship with the boyfriend/girlfriend and respond in repentance or will “end” the relationship with God and run away from Him.  “Sin always aims at the utmost.”

What is the answer?  Kill the flea.  Kill the sin.  As John Owen has aptly said, “Be killing sin, or it will be killing you.”  Yes, Christ has ultimately taken away the principle of sin and its effects.  But we are still called in Scripture to actively be engaged in killing sin.  I do not fully understand it but all I know is this: Jesus has killed sin, Jesus is killing sin, and Jesus will ultimately do away with sin and he is calling us to, by his power, engage in killing sin. 

So, no matter how big or small the sin might seem to be it needs to be repented of.  Believe the gospel enough to turn from the ugliness of sin and embrace the beauty of Christ.  A couple fleas can end up costing you lots of labor and money; a “little sin” can cost you your soul. 

If you have never read John Owen’s classic work The Mortification of Sin, I would strongly suggest buying a copy for only 6.30 and reading it.