Genesis is the first book of the Bible. It is also the book of beginnings because it tells us the origins of life and accurately explains the main problem of the world--Sin.
From the first two chapters of Genesis, we are made to know there is a Creator who created the world and all that dwells in it (Genesis 1:1, 31, 2:26-27). After creation, God saw that everything He had created was good (Genesis 1:31). But today, in contrast to Genesis 1:31, the world in its current state is not good. It is a world filled with pain, tragedy, wickedness, cruelty and every horror imaginable. How do we reconcile the current state of the world with God's proclamation that "everything that he had made...was very good". The answer is that sin entered the world. So;
What Is Sin?Sin is any want of conformity unto, or transgression of, the law of God [a]. Lev 5:17; Jas 4:17; 1 John 3:4~Westminster Shorter Catechism Q14
In these words we see what sin is. Sin is breaking God's law by omission or commission. In modern English, the words, "want of conformity" will read something like inability to conform to the law of God or failure to measure up to or obey God's command. In Greek, the word hamartia is used in explaining what sin is. Sin is "missing the mark" and rightly so, we are all sinners because we have missed the mark of God's rigtheous standard (Romans 3:23).
Now, how did sin enter the perfect world God created? We again go back to Genesis, the book of origins. In Genesis 2:16-17, we read of a commandment God gave Adam, the first created man, "And the LORD God commanded the man, saying, “You may surely eat of every tree of the garden, but of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall surely die". Fast foward to Genesis 3, Adam disobeyed God; he ate of the forbidden tree and by that act of disobedience, sin entered the world.
Adam in the garden of Eden was acting as a federal head for all of humankind therefore his fall became the fall of all who will ever walk this earth: "Therefore, just as sin came into the world through one man, and death through sin, and so death spread to all men because all sinned"(Romans 5:12).
Except Jesus who lived a perfect life without sin, all humankind inherited the consequences and effects of Adam's fall; physical and spiritual death. Our nature was badly corrupted and we were alienated from God. The Psalmist said "Behold, I was brought forth in iniquity, and in sin did my mother conceive me" (Psalm 51:5).
What he means here is that he was born with a sin problem. He inherited sin. We are by ourselves unable to please God: "None is righteous, no, not one; no one understands; no one seeks God. All have turned aside; together they have become worthless; no one does good, not even one.” (Romans 3:11-12). These words describes the helpless state of humankind without Christ. They are enemies of God, separated from Him and guilty of eternal damnation.
However God didn't leave sinners to our fate to try to work our way to Him. God made the first move towards reconciling sinful humankind to Himself. If you read Genesis 3 again, we see that even in their sins, God's mercy was manifested. Firstly, God proclaimed what theologians refer to as protoevangelium--the first gospel. God announced His plans towards reconciliation. A curse was pronounced and a remedy for that curse was also revealed:
I will put enmity between you and the woman, and between your offspring and her offspring; he shall bruise your head, and you shall bruise his heel (Genesis 3:15).
The seed of the woman being referred to here is Christ who the Bible speaks of by saying "The reason the Son of God appeared was to destroy the works of the devil"(1John 3:8). The works of the devil is sin that separated us from God. And it is this, Jesus died to destroy. He took the punishment that belonged to sinners. He died in our place to appease for our sins and reconcile us to the Father. Our sins was imputed to Him. He became our substitutionary atonement (Isaiah 53:5-6).
Secondly, God covered the nakedness (guilt and shame) of Adam and Eve revealing a type of Christ's imputed righteousness to those who will come to Faith through Jesus Christ. Paul aptly captures this saying, "For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God" (2Corinthians 5:21).
Christ was murdered on the cross because of the sins of you and I. And He resurrected to give eternal life to all who will come to Him in Faith If you have not come to saving faith through Christ, you are condemned to eternal damnation and an enemy of God. One day, you will have to answer for your sins before a Holy God and nothing you will present will measure up to God's Holy standard. Your good works outside of Christ are like filthy rags. Repent from your sins and turn to Christ for forgiveness.