If someone were to ask you, “What’s the most dangerous spiritual responsibility to neglect?” You might think of Scripture reading, prayer, evangelism, listening to preaching, or attending corporate worship. And it’s not that you’d be wrong…God commands all believers to pursue those things. They’re non-negotiable.
But there’s another spiritual responsibility we often overlook. It’s an intimate, unpleasant, and exhausting duty—killing sin. Maybe that’s a provocative thing to say, and some might want to challenge it. After all, didn’t Christ deliver a crushing blow to sin when He rose from the dead? Wasn’t it His job to kill sin at Calvary? Well, yes, and that was the fundamental beginning to His judgment against sin.
Christ removed the penalty of our sin on the cross. As Christians, you and I no longer stand accused under the righteous requirements of the law (Romans 8:4). There’s no condemnation to those who are in Christ Jesus (Romans 8:1). The work of Christ also removed sin’s power over believers. Having been crucified with Christ, we’re no longer enslaved to sin’s grip. Christ rendered it powerless when He rose from the dead (Romans 6:14, 22). So if Christ removed sin’s penalty and power, what’s left to kill?
Too few Christians are asking that question today, and too few pastors are bringing it to their attention. That wasn’t true of Puritan pastor John Owen. He dealt comprehensively with the question, teaching Christians from Scripture how to kill remaining sin. In one of his classic works, The Mortification of Sin, there’s a famous quote from Owen I’ve never forgotten: “Be killing Sin, or sin will be killing you.” That’s right—kill or be killed. Take your pick.
Thankfully, other faithful pastors followed in Owen’s footsteps to expound on the Bible’s teaching on the believer’s relationship to indwelling sin. They understood the reality of remaining sin, took its threat seriously, and labored to help the body of Christ adopt biblical strategies for killing it. We owe the Lord a deep debt of gratitude for them for helping us with such practical issues in our sanctification.
It was about five years ago through the “Grace to You” podcast when I heard what proved to be one of the most impactful and helpful messages from John MacArthur. The sermon was called, “Hacking Agag to Pieces,” and it aired as part of the sermon series, Dealing with Sins of the Mind. I remember the powerful analogy John made in that sermon; he compared the remaining sin in the life of a believer with King Agag, the wicked ruler of the Amalekites in the Old Testament.
As the story goes, God sent Samuel to rebuke King Saul because he allowed Agag to live in disobedience to His command to annihilate the Amalekites. Samuel announced the end of Saul’s throne, and then turned to Agag to take care of a more gruesome business. Samuel hacked Agag to pieces with a sword.
I’ve never forgotten that graphic illustration of how serious God is that we be relentless to pursue and put to death every remaining sin in our lives. Here’s John’s conclusion to that message:
When Agag comes to you cheerfully and says, "Surely the bitterness of death is past," which is another way of saying, "Well the war is over, you're saved, you're on your way, I'm defeated, don't worry about me." When Agag and his Amalekite friends want to make friends with you and declare an end to hostilities, that's when you grab your sword and hack them to pieces.
As believers, indwelling sin continues to trouble us, but God calls us to treat that remaining sin like Samuel treated Agag. Kill it. Be brutal about it. But how do we do that? That’s the question we’ll explore in the next post, with the help of the Apostle Paul, John Owen, and John MacArthur. Sound good? Stick around.
Until then, be killing sin, or sin will be killing you.