Various terms are used in Scripture to describe sin. The most common term in both the Old and New Testaments means to miss the mark, i.e., the righteous standard of God. That such failure is more than mere weakness is seen in other terms that signify rebellion and willful violation of the holy. The basic nature of sin is revealed in the first human sin (Genesis 3). There its essence has been interpreted primarily as unbelief seen in the rejection of God's word or pride in choosing to be as God. Both of these concepts (unbelief and pride) are central to the essence of all sin, which may thus be defined as the willful choosing to be autonomous rather than living by faith under God. Sin results in alienation and separation from God, who is the only source of true human life. The result is death, which is not only viewed as the natural result of sin, but even more as the judgment of God. The full awfulness of sin's effect is revealed at the cross, where Jesus suffers the wrath of God in the abandonment of the Father for human sin.
The effect of Adam's sin has come to all humans as his descendants, so that all mankind is burdened with sin from birth. This sinful state is usually identified as "original sin" (cf. Romans 3:23; 5:12-19). The death of Christ for human sin and His sinless life of perfect fellowship with the Father are accounted to those who by faith are joined to Him thus overcoming the alienation of sin.
This topic is from the Lockman Foundation.