As far as it compares to the holiness of God, all sin is the same. Every sin, from anger to murder, from white lies to adultery, will lead to eternal condemnation (James 4:17; Romans 6:23). All sin, no matter how “small,” goes against the nature and will of an infinite and eternal God and is therefore deserving of an infinite and eternal punishment (Isaiah 13:11). In this sense, there is no “worst” sin.
So, there is no “worst” sin in that all sins are, by nature, sinful. All sinners fall short of the glory of God (Romans 3:23). But, considered another way, sins are unequal in at least two respects:
First, not all sins are equal in their earthly consequences. Although both lust and adultery are sinful, one (adultery) will have worse consequences than the other. The consequences of having lust in one’s heart will not be as severe as committing the physical act of adultery. The same is true with entertaining a covetous thought versus committing theft. All sin is bad, but not all sin carries the same penalty in this world. In that sense, some sins are worse than others.
Scripture singles out sexual sin as having a unique impact on the sinner: “Flee from sexual immorality. All other sins a person commits are outside the body, but whoever sins sexually, sins against their own body” (1 Corinthians 6:18). In this passage, immorality is placed in a category apart from other sins as having a direct effect on one’s body. Does this mean sexual sin is the “worst” sin? Maybe. It certainly means that sins involving sexual immorality have worse consequences in this world.
Second, not all sins are equal in the degree of eternal penalty. Illustrating the need to be ready for His return, Jesus spoke of different degrees of punishment: “A servant who knows what the master wants, but isn’t prepared and doesn’t carry out those instructions, will be severely punished. But someone who does not know, and then does something wrong, will be punished only lightly” (Luke 12:47– 48, NLT). So, sins of presumption and negligence warrant a heftier penalty in the final judgment than sins committed in ignorance. Hell is hot, but it might be hotter for some. In that sense, some sins are worse than others.
We should guard ourselves against three wrong ideas about the “worst” sin:
First, if there is a “worst” sin, that doesn’t mean that other, “lesser” sins are excusable. Sin is sin, and it is all unrighteous.
Second, we must not fall into the trap of comparing our sins with others’. When we compare, we will invariably conclude that other people are committing “worse” sins than we are; our sins are somehow “better.” Our first concern should be our own sin, whatever it is, and not the sins of those around us (Matthew 7:4–5). God’s standard is not how well we measure up to other people but how we measure up to Christ.
Third, even if there is a “worst” sin, God can still forgive it. Just as there is no sin too small to be worthy of punishment, there is no sin too big that God cannot forgive it. When a repentant prostitute came to Jesus, she found grace; Jesus then said to the onlookers, “I tell you, her sins—and they are many—have been forgiven” (Luke 7:47, NLT). And God has already forgiven the man who considered himself to be “the worst of them all” (1 Timothy 1:15, NLT). Jesus died to pay the penalty for all sin (John 3:16; 1 John 2:2). “God made [Jesus] who had no sin to be sin for us, so that in him we might become the righteousness of God” (2 Corinthians 5:21). For the believer, there is no sin Jesus’ sacrifice does not cover (see Romans 8:1).
God hates sin. Thankfully, He has provided a way to “cleanse us from all unrighteousness” (1 John 1:8–10) through His Son, Jesus Christ (John 3:17). Our Heavenly Father “desires all men to be saved and to come to the knowledge of the truth” (1 Timothy 2:4).
In the final analysis, we might say that the “worst” sin is unbelief. Faith in Christ is how people rightly respond to God’s offer of salvation. “How shall we escape if we ignore so great a salvation?” (Hebrews 2:3). To reject the Savior is to accept the penalty for one’s own sin.