Sin is one of the first words we learn as Christians, and one of the last words a non-Christian wants to hear from the pulpit. Yet if we do not introduce the reality of sin, we have not adequately shared the gospel. Scripture teaches that sin is rebellion against God (Isaiah 1:2), and it carries real consequences. Sin's consequences fall differently on the believer than on the non-believer.

What is Sin?

At its root, sin is any failure to conform to the character of God. This failure comes through thought, word, deed, desire, or action (Matthew 5:28; James 4:17).

Everyone who commits sin practices lawlessness; and sin is lawlessness.

-1 John 3:4 CSB

Sin isn't just "doing bad things," sin is missing the mark of God's glory and failing to love Him fully (Mark 12:30), failing to trust him completely (Hebrews 11:6), and failing to reflect His character as we were made to do (Genesis 1:27). This failure is not the mark of wicked few people, it is the condition of every human being (Romans 3:23).

Where Sin Came From

Genesis 3 records humanity's first sin: Adam and Eve disobeyed God's instructions and ate from the one tree God has told them not to eat from (Genesis 3:1-6). God was clear about the stakes associated with this disobedience:

"But you must not eat from the tree of the knowledge good and evil, for on the day you eat from it, you will certainly die.

-Genesis 2:17 CSB

God's warnings are never empty threats. Because Adam represented the whole human race, his sin brought sin onto the whole human race.

Therefore, just as sin entered the world through one man, and death through sin, in this way death spread to all people, because all sinned.

-Romans 5:12 CSB

Every person is born into the world already broken by sin, and every person contributes to that brokenness through their own sin (Psalm 51:5).

The Universal Guilt of Mankind

“There is no one righteous, not even one…There is no one who does what is good, not even one.”

-Romans 3:10–12 CSB

As W.A. Criswell preached in a sermon from 1954: "Culture and religion can dress up the outside of a life without touching the heart underneath. The refined churchgoer whose heart has not been transformed, and the dissolute skeptic are, in God's sight, alike lost. This is total depravity: not that everyone is as wicked as possible, but that sin has penetrated every part of human nature."

For all have sinned and fall short of the glory of God.

-Romans 3:23 CSB

The Consequences of Sin

Sin's consequences are threefold. First, separation from God.

“But your iniquities are separating you from your God, and your sins have hidden his face from you so that he does not listen.”

-Isaiah 59:2 CSB

Second, death. Spiritual, physical, and eternal separation from Christ.

For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord.

-Romans 6:23 CSB

Third, judgment.

And just as it is appointed for people to die once — and after this — judgment

-Hebrews 9:27 CSB

These are not arbitrary consequences, but the outcome of rebellion against the source of life itself (Romans 1:18). Consequences differ entirely based on a person's relationship to Jesus Christ.

The Consequences for the Non-Believer

For those who reject Christ, sin's consequences remain fully in force (John 3:36). Jesus said the verdict already stands:

“Anyone who believes in him is not condemned, but anyone who does not believe is already condemned, because he has not believed in the name of the one and only Son of God.”

-John 3:18 CSB

The Bible's Second Epistle to the Thessalonians describes unbelief's outcome as eternal destruction and separation from God's presence:

When he takes vengeance with flaming fire on those who don't know God and on those who don't obey the gospel of our Lord Jesus. They will pay the penalty of eternal destruction from the Lord's presence and from his glorious strength.

-2 Thessalonians 1:8–9 CSB

Revelation calls this "the second death." Not annihilation, but conscious, everlasting destruction:

Death and Hades were thrown into the lake of fire. This is the second death, the lake of fire. And anyone not found written in the book of life was thrown into the lake of fire.

-Revelation 20:14–15 CSB

For the non-believer, sin's consequences are not disciplinary but final; no atonement stands between the sinner and the penalty deserved (Hebrews 10:26-27).

The Consequences for the Believer

For the one who trusts Christ, the picture changes. This change is not from sin going away, but because the penalty for sin has been paid (Colossians 2:13-14).

Therefore, there is now no condemnation for those in Christ Jesus.

-Romans 8:1 CSB

This does not mean that Christians do not sin (1 John 1:8). The consequence has shifted from condemnation to fatherly discipline, meant to keep us in God's will.

For the Lord disciplines the one he loves…

-Hebrews 12:6a CSB

Christians can still reap painful, temporary consequences: broken relationships, wasted years, church discipline (Matthew 18:15-17), because sowing and reaping still occur in the life of the Christian.

Don't be deceived: God is not mocked. For whatever a person sows he will also reap, because the one who sows to his flesh will reap destruction from the flesh, but the one who sows to the Spirit will reap eternal life from the Spirit.

-Galatians 6:7–8 CSB

Discipline is a demonstration of God's mercy. God is sparing us from the world's fate (1 Corinthians 11:32). When we confess our sins to God, He restores us.

If we confess our sins, he is faithful and righteous to forgive us our sins and to cleanse us from all unrighteousness.

-1 John 1:9 CSB

Conviction is the Christian's Guardrail

The reason a Christian's sin and its earthly consequences are checked before they can go too far is the Holy Spirit's indwelling. Every believer is sealed by the Holy Spirit.

In him you also were sealed with the promised Holy Spirit when you heard the word of truth, the gospel of your salvation, and when you believed.

-Ephesians 1:13 CSB

The indwelling of the Holy Spirit is the mark of a person who belongs to Christ.

You, however, are not in the flesh, but in the Spirit, if indeed the Spirit of God lives in you. If anyone does not have the Spirit of Christ, he does not belong to him.

-Romans 8:9 CSB

The Holy Spirit grieves when a believer sins (Ephesians 4:30) and actively battles against the flesh from within.

I say, then, walk by the Spirit and you will certainly not carry out the desire of the flesh. For the flesh desires what is against the Spirit, and the Spirit desires what is against the flesh; these are opposed to each other, so that you don't do what you want.

-Galatians 5:16-17 CSB

That inward resistance to sin is conviction, and it's God's mercy at work in the Christian. It is a discomfort that presses the believer toward repentance before the sin can metastasize into earthly consequences. The Old Testament King David describes this pressure vividly when he was in a season of unrepentant sin:

“When I kept silent, my bones became brittle from my groaning all day long. For day and night your hand was heavy on me; my strength was drained as in the summer's heat.”

-Psalm 32:3–4 CSB

This misery being described is not punishment, it's the Holy Spirit's conviction doing its work. Conviction drove David to repent and be forgiven rather than continue in sin, and it will do the same for every Christian.

The non-Christian has no internal guardrail of Holy Spirit conviction. Because the Holy Spirit does not indwell those who are outside Christ (Jude 19, 1 Corinthians 2:14), sin can run its natural course, hardening the heart rather than convicting it (Ephesians 4:19).

This is one more way the believer and the non-believer are different. Not that the believer never suffers sin's earthly consequences, but that the Holy Spirit's conviction will warn us not to continue in sin, pushing us toward repentance and restoration rather than allowing us to run all the way into the ditch.

Christ Makes the Difference

Because sin is a universal problem, the answer is offered universally to every kind of sinner on the same terms. Remember when the earth was destroyed by flood, every creature entered the ark through one door (Genesis 6:16). At the Passover, a family's safety depended on the blood on the front door, not on merit (Exodus 12:13).

God intentionally gave us one way to be saved from the eternal consequences of sin.

For everyone who calls on the name of the Lord will be saved.

-Romans 10:13 CSB

The self-righteous and the immoral, the unregenerated churchgoer and the athiest, all stand in the same need and are offered the same door (Acts 10:34). There is no easier news to understand, and there is no one too far gone for the gospel. Sin's eternal consequences have already been paid in full for everyone who trusts in Jesus Christ.

He himself bore our sins in his body on the tree; so that, having died to sins, we might live for righteousness. By his wounds you have been healed.

-1 Peter 2:24