Paul explains why humanity is without excuse before God.  We can know enough about God, from what we see in what He created, to humbly bow before Him and worship.  But we are bent toward going our own independent way.  Rather than bow and worship we redefine God to fit our self-determined idea of god.  This independent streak is sin and leads to increasing degrees of sinful behavior.  What we believe impacts our behavior and attitude.

For those who are religious and think they’re better than others, Paul further develops his argument in chapter 2 that all are sinners.  We’ll be judged by how we judge others.  God’s kindness, tolerance and patience are designed to lead us to repentance.  But if we show contempt for these overtures of God we’ll store up wrath against ourselves for the day of God’s wrath, when His righteous judgment will be revealed. 

Amplifying this truth further in chapter 3 Paul recounts statements made throughout the Old Testament to illustrate our propensity to do evil and resist righteousness.  There is none who seeks God, not even one. 

As Paul comes to the conclusion of this first main section he summarizes his argument of the universal need for salvation by saying, “All have sinned and fall short of the glory of God.”  That’s our need for God’s Salvation.