The bible explains the human condition. It explains why we do what we do, and what God has done to rescue us out of our condition.
When the bible speaks of God saving us, part of what we’re being saved from is our broken status as works based self-justifiers. Since we’re made in God’s image, we’ve got the moral law of God written on our consciences. This law is summarized in the 10 commandments, and is further summarized as loving God and neighbor. We see this law at work when even an atheist jumps into a freezing pond to save someone he doesn’t know. John Calvin points to that kind of example and explains that by doing this he is simply responding to the law written on his heart to love his neighbor. One could even say that earth worship done by some Druidic pagan is seeking to love God, though it’s redirected to a more abstracted universal concept or transcendent deity. We know that man is built to worship, whether it’s a football team, beauty, or a god of his own making.
We also see the principle at work in people who can’t or don’t ever apologize have a righteousness (an I’m-good-enough) of their own that they’re trying to achieve or maintain. Their self-worth is 
based on performance, and internally it would crush them to admit that they’re a failure. The internal lawyer that accuses them is so strong that to give in and admit that the lawyer is right is a horror that they simply cannot face. If these people are Christians, they have not been taught, or they refuse to give up what they “bring to the table” and simply rest in Christ’s righteousness for them. Theirs is a type of treadmill Christianity where Christ forgives them, but they’re looking to sanctification to be a place to silence the lawyer. Often comparing themselves with others becomes the standard.
For the unbeliever, they have nothing to rest in, but must continue on that treadmill where they try to fill that black hole of their own lack of enoughness, and so they must also find a group of others that they can compare themselves to and come out looking better than. This is the human condition. The condition of mankind who has the law written on the heart, it came from Adam who was made for works-based righteousness.
Biblical Christianity, (which is Reformed Christianity with a proper covenant theology) understands and can explain the human condition. We know why people (including ourselves) do the things we do. There is this craving to do something and be declared righteous for it. To “do this and live”, or at least be enough. This is why many Christians tend to regard sanctification as leaving vice and doing virtue. What they don’t understand is that true sanctification (set-apart-ness) includes the forsaking of our own righteousness and resting in Christ’s righteousness. That is what happens in large part at conversion. If a person has not forsaken their own righteousness to rest in Christ’s alone, they’re not understanding or believing the saving good news.
Because of ignorance it’s historically been the morally conforming conservative do-gooders that appear to be good Christians, when it reality they might not be converted at all. Today left-leaning do-gooders who virtue-signal tend to consider themselves better than others (or at least good enough) because they’re woke, meaning they hold the correct social or political views. This new and culturally attuned Christianity is rapidly replacing the old-school type psudo-Christianity. This new brand of “I’m right by what I do” Christianity is based on a sort of lock-step common conscience, monoculture of wokeness. They make these values (Which also happen to be American political wedge issues) objective measures of true Christianity. Therefore those who are woke, those who hold these “right positions”, they’re the righteous ones. It’s the equivalent of saying “…and Abraham believed in the doctrines of wokeness and it was reckoned to him as righteousness.” If not doctrinally at least functionally they’ve renegotiated justification based on an insistence of a conscience binding woke-sanctification. This is not Reformed theology.
Historic Reformed theology is a way to understand most of the reasons why we do what we do, because it is an understanding of the bible’s covenantal themes. Reformed theology is Covenant Theology, which is the underlying doctrine of the great exchange. That is the good news of the imputation of our sin to Christ, which is born away on the cross, and Christ’s righteousness imputed to us. We are to rest not in our sanctified selves, but only in Christ’s righteousness for us. Any evangelical obedience (the relative obedience that we do to the law as Christians) is out of the motive of gratitude alone, because there is no merit in them to either lose or gain, as Christ and His work alone is our righteousness. Christ’s obedience and sacrifice secures eternal life, and heaven for us, because we are united to Him, and so His resurrection was our judgement day. His death and resurrection was a judgement day event where we died positionally with Him and were raised again positionally with him, and are now seated positionally with Him. That is our definitive sanctification. It is a reckoning or counting towards (imputation) one who is a substitute from or to another. Christ is our substitute who died for us, and our substitute who lived righteously for us. So, in Christ, we’re not simply pardoned sinners, but God counts us as if we’ve loved Him with all our hearts and our neighbor as ourselves. This is what it means to be justified. It’s irrevocable, because it was earned entirely outside of us by Christ, and given to us (who believe) as a gift.
This is how a holy God is reconciled to and saves sinful mankind out of our miserable self-justifying (yet failing to be truly righteous) condition, by giving us Christ as our representative. Through the instrument of faith alone (that is believing and trusting in Christ and the promises of God in Him) God unites us to Christ and tells us because of that Christ bore our failure to be righteous away on the cross, and Christ also earned a perfect righteousness for us by His whole obedient live lived. By doing so. Christ fulfilled the covenant of life (covenant of works) that our first representative Adam did not, and so He has secured the promises of eternal life and the blessings of God.
It is through the explaining of doctrine, (that is the normal means of the preaching of the word of God) particularly the gospel I just explained that God uses to, by His spirit grant us faith so that we trust in Christ. So, this same gospel that justifies us is to continue to be examined and explained each week in all its’ glorious detail so that we are built up in Christ, and our faith is strengthened. That is why Historic Reformed piety is church centered, and particularly the “means of grace” centered, which is word and sacrament. Word (law and gospel, and particularly gospel) and sacrament, and then as we have offspring, we baptize them and we moms and dads catechize them (teach them the faith) as they are covenant members of the Christ confessing community of believers.
This is Reformed theology, it explains the human condition, offers
A Reformed understanding of the bible explains the human condition, understands the escape from wrath and judgement through salvation in Christ, as well as the preservation and building up of ones faith through a God ordained community of Christ professing believers until we are brought into glory and our inheritance. There is an answer for our natural tendency to self-justify, a way to answer the inner-lawyer with Christ’s perfect righteousness. As the church proclaims the good news of the outside-of-us righteousness of Christ, we believe it, and rest in it. That is repentance from our own efforts to be enough, and we turn to and rest in Christ alone. Then when we’re freed from that bondage, by God’s Spirit we are enabled to follow our new nature, as we are a new creation in Christ, seeking obedience from the heart, out of the motive of gratitude alone. Therefore, we are definitively and objectively freed from the penalty of sin, and also continued to be experientially and subjectively freed from the power of sin.