The phrase "all have sinned" is taken directly from Scripture. In the New Testament book of Romans chapter 3 verse 23, the apostle Paul states, "All have sinned and fall short of the glory of God." Looking at the verse in the context of chapter 3 and the larger context of the entire book of Romans, it is clear that Paul is making the point that Gentiles and Jews are alike in that all are sinners. The advantages enjoyed by the Jews, such as having been entrusted with the oracles of God, do not exempt them from the charge of sin (Romans 3:2, 9). For they sinned against the law (Romans 2:12). Furthermore, the fact that the Gentiles (the rest of humanity) did not possess the Mosaic law does not exempt them from the charge of sin either. For the Gentiles sinned against the law of God which is written on our hearts (Romans 2:14–16). The bottom line is that no one is without sin, no one is righteous (Romans 3:10). Belonging to a specific group, whether it be nationality, ethnicity, religious affiliation, or a socio-economic or political class spares no one of the charge of being guilty of sin. In fact, all human beings descended from Adam (the whole human race) are born under the power and the curse of sin (Romans 3:19; 11:32).
All have sinned – What does that mean?
There is but one exception. His name is Jesus Christ and He was born of a virgin and conceived by the Holy Spirit (Matthew 1:20–23). He is not a mere mortal man. He is the God-man. The second Person of the triune God. God in the flesh (John 1:1, 14). It is Jesus Christ and He alone is able to rescue sin-enslaved humanity. That is the very reason He left heaven and came to earth (Philippians 2:5–8).—to save sinners (1 Timothy 1:15).
Sinners is what we are. Whether male or female, rich or poor, we are all sinners. We have all been born with a sin nature and we all sin. To sin is to violate God's law and therefore to dishonor Him. We sin when we do what God prohibits (sins of commission) and when we fail to do what God commands (sins of omission). Sin is not merely external but extends even to our innermost soul, our hearts (Matthew 15:19). By breaking the law at even one point, we are guilty of breaking it all (James 2:10). By sinning in our hearts we have fallen short of the glory and righteousness of God. The just desert or wages of sin is death (Romans 6:23). Therefore, we are born condemned and increase our guilt with every sin. The only way to rectify this deplorable condition is to be perfect, which we are both unable and unwilling to do.
Amazingly, graciously, God sent His sinless Son to fulfill the righteous demands of the law which we have failed to fulfill and to suffer the wrath that our sins merit (Romans 5:6–9). Through faith in Jesus, we who are sinners are declared righteous before God (2 Corinthians 5:21). Not a righteousness of our own but the righteousness of Christ that we receive through believing in Him (Romans 3:21–22). So, yes, we have all sinned, but because the sinless One suffered the punishment for our sins and offers us His righteousness as a free gift, we who are sinners can be called saints.
The sin nature - What is it?
Does the Bible have a list of sins?
Are all sins equal?
The consequences of sin - What are they?
How can I get right with God?
Truth about Sin