All of us are sinners. Bible.org explains it this way: if one person goes into a deep valley, and another person stands on a high mountain peak, they are both still very far from the moon. There really is no difference. In other words, we all fall short of God`s glory (Romans 3:23). There`s a funny saying in another culture, in which they call the middle of nowhere "the place close to the moon." But in fact we are all far from the moon, far from the sun, and far from God`s glory. We are all "missing the mark." We are all sinners.
Today`s world asks why we call something "sin." Society brazenly questions the traditional morality and ethics of the Bible. The late pastor Tim Keller described it this way: people nowadays pretend to be "nonjudgmental" while imposing their own personal moral beliefs on others -- but this is highly self-contradictory. This hypocrisy in modern thinking demonstrates that where an absolute reference point doesn’t exist, then all moral beliefs become equally invalid.
Moral beliefs are only valid because God exists. People ask, why do you call something "sin" and treat it as bad? Sin is bad because it separates us from God, contradicts God`s will, and also undermines human flourishing. That`s why Apostle Paul described sin as "ungodliness AND unrighteousness." When we lose God, then all decency and standards break down.
Ultimately, this is why we need Jesus. Because we are all sinners who are far away from God and are headed toward destruction -- but Jesus died in order to reconcile us to God. I hope that we could remember how serious sin is, and therefore how important it is to believe in Jesus. Only Jesus Christ can save us from our sins.