Sin is a difficult topic to discuss theologically because the same word in English refers to several different states. In its most basic form, sin is a transgression of law and rebellion against God. Sin is any action that harms the relationship we have with God and/or another person. It is choosing to act in a way that pulls us away from God. He designed us to respond to Him in a way that is in agreement with His nature. Sin breaks that connection, refuses that gift, and rejects God.
What is sin?
Sin entered the world when Adam ate from the tree God had prohibited. We are now spiritually sinful because of the "sin nature" we inherited from Adam. We are born with the nature of sin and a natural tendency to sin. We are born with the inclination to reject God. Because of our identity as descendents of Adam, we also carry "imputed sin." This is a financial or legal term meaning taking something that belongs to someone and crediting it to another's account. It is almost like being a fan of a certain team because they are the only team in town. We are identified with that team, which in our case is sin. Of course, sin is also each individual action which is counter to God's law.
Sin can manifest in many different ways. The Hebrew 'awon means an iniquity or malevolent unfairness (1 Samuel 20:1). Rasha' infers restlessness or something that is out of control (Isaiah 57:21). Chata' is the most commonly heard definition. It means missing the mark or straying off course (Judges 20:16). 'Abar means to transgress or to go beyond that which is sanctioned (Judges 2:20). In the New Testament, the Greek hamartia is similar to the Hebrew chata' but it goes further. It is not only "missing the mark," but also the inner compulsion or nature that induced the offense (Romans 6:1). Similarly, it can be an organized power that deliberately sets about causing a person or group to fall into sin (Romans 6:12).
Since all sin is the rejection of God, His authority, and His preference, sin automatically excludes us from His presence. But forgivness of sin, as well as grace and peace and eternal life in paradise are only found in God. Freedom from the grasp of sin is only found in God. Our inherited sin nature, our imputed sin, and our every little choice definitively separate us from God. Fortunately, Jesus' sacrifice covers all sins. Instead of Adam's imputed sin, we receive Christ's imputed righteousness (2 Corinthians 5:21)—we choose another team to identify with. As the Holy Spirit indwells us, the sin nature loses its grasp, and we are no longer its slave. And when we commit individual acts of sin, we are authorized to approach the throne of grace with confidence (Hebrews 4:16), knowing that coming to God and confessing our sins will allow us to renew our relationship with Him.
The sin nature - What is it?
The consequences of sin - What are they?
How can I know what is a sin and what isn't?
Does my private, personal sin affect others?
How do I receive forgiveness from God?
Truth about Sin