Posted On December 6, 2019

Be Killing Sin – Part 1

by | Dec 6, 2019 | Theology

In his work on the Mortification of Sin, that is, the killing of sin, John Owen (1616-1683) writes:

“Do you mortify; do you make it your daily work; be always at it whilst you live; cease not a day from this work; be killing sin or it will be killing you.”

Be killing sin or it will be killing you. Owen bases his work on the mortification of sin off of Romans 8:13. But we find a biblical precedent for killing sin much earlier than Paul’s letter. In fact, we see it in the very first book of the Bible in God’s confrontation with Adam and Eve’s firstborn, Cain (Genesis 4:6-7).

God’s Rebuke

Moses records in Genesis 4:6 Yahweh’s question to Cain: “Why are you angry, and why has your face fallen?” We know that God already knows the answer but He confronts Cain with a gentle, yet firm rebuke. It is a wonder that we often forget that not only is God a speaking God but that He is good to us to reveal His thoughts and desires.

And even though I’ve labeled this as God’s Rebuke, let us also consider the grace that is in it. God comes to a sinner, an unbeliever, in mercy. Horatius Bonar says of these words: “There is no wrath in them, as we might have expected. It is the voice of long-suffering and compassion. It is grace that is dealing with the sinner.” Even in God’s rebuke, there is mercy here as He confronts Cain.

Now let me also reiterate this: I called Cain an unbeliever and so he is. What I don’t mean is that he didn’t believe in God. Of course, Cain believed in God. Here God is speaking to him! When I call Cain an unbeliever I mean that he had no saving faith in the goodness and promises of God. You see, we see throughout the Bible people who believed in God, but weren’t people of faith. Cain is the first example, but there are others.

And so let me remind us that believing in God really means nothing if you are not trusting Him in saving faith. God is a speaking God and has revealed His thoughts and desires to us in His precious Word. And we must not be like Cain and only affirm these truths in our brain. We must cling to God’s promises in faith.

God’s Delight

The Lord goes on to say, “If you do well, will you not be accepted?” (Genesis 4:7). Doing well has a moral connotation. It is doing right. God delights in righteousness. God delights in righteous deeds.

Why? Because He is righteous. God delights in Himself. God delights in moral perfection. God delights in holiness.

This is why God accepted Abel and not Cain. Because in God’s eyes, Abel was righteous. Why? Because Abel trusted God’s promises for a deliverer. The Scriptures tell us that Abel offered his sacrifice by faith (Hebrews 11:4).

Since God’s delight is in holy perfection, He delights in His Son Jesus. And since Jesus bore our sin debt and rose again from the dead, by faith in Him we too can be accepted by God. In fact, that is the only way we can be accepted by God. God has not given an unfair stipulation to Cain. God is not required to accept what He does not delight in.

God’s Disgust

Finally, the Lord finishes His dialogue with Cain with, “And if you do not do well, sin is crouching at the door. Its desire is contrary to you, but you must rule over it.”

God hates sin. And God gives Cain here an important warning about sin. We will get into that more in a future post. But we need to note something here: Good deeds that are tainted with sin are not good deeds.

Some people think they can do more good deeds than bad deeds and that will get them to heaven. But God is the standard of goodness. Cain, himself, does a “good deed,” if you will, in bringing an offering to the Lord (Gen. 4:3). But this good deed is not “doing well” for it is centered on Cain and not God.

This makes me think of Lord’s rebuke to His people Israel and their faulty worship in Isaiah 1:12-18:

“When you come to appear before me, who has required of you this trampling of my courts? Bring no more vain offerings; incense is an abomination to me. New moon and Sabbath and the calling of convocations—I cannot endure iniquity and solemn assembly. Your new moons and your appointed feasts my soul hates; they have become a burden to me; I am weary of bearing them. When you spread out your hands, I will hide my eyes from you; even though you make many prayers, I will not listen; your hands are full of blood. Wash yourselves; make yourselves clean; remove the evil of your deeds from before my eyes; cease to do evil, learn to do good; seek justice, correct oppression; bring justice to the fatherless, plead the widow’s cause. “Come now, let us reason together, says the LORD: though your sins are like scarlet, they shall be as white as snow; though they are red like crimson, they shall become like wool.”

In this passage, God offers both the problem and the remedy. Like Cain, Israel had chosen to worship the Lord but with sin. Their hearts were not in it. And God rebuked them and offered to wash their sins away and make them like snow.

But they must trust Him. This is the same exhortation today: God hates our sin. If we think we can appease God with good works we are wrong. Rather, we must seek His cleansing that comes only by faith in Christ.

In the next post, we will examine more the dangers of sin.


See all posts in this series

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  1. Be Killing Sin - Part 2 » Things Above Us - […] Last time, we looked at God’s rebuke of Cain and the exposure of his sin (Genesis 4:6-7). In this…