Sin is defined as anything that separates us from God. You see God created man to praise, worship and glorify him. God does not need us, but he wants us. When Adam and Eve ate from the tree they separated man from God. The price of their disobedience was death. Paul says in Romans 5:12 "Therefore, just as sin entered the world through one man, and death through sin, and in this way death came to all men, because all have sinned". That means as humans we are by default sinners. Let's look at what God says through Paul in Romans 7:14-25. He writes "For we know that the law is spiritual; but I am unspiritual" (because of sin) "sold as a slave to sin." (Matthew 22:36 says that Love  for God is the ultimate law, and if we keep this we will keep all others as well). " I do not understand what I do. For what I do, I do not want to do," (even Paul was not perfect and had problems not sinning. I know I do) " What I hate I do. And if I do what I do not want to do, I agree that the law is good.  As it is, it is no longer I who do it, but sin living in me." As a Christian we are no longer sinners by nature, because we have been conformed to the likeness of Christ who was perfect. Are we still responsible? By all means, yes! God does not excuse us our actions. Now however we have Christ to go for forgiveness. "I know that nothing good lives in me, that is, in my sinful nature." (which will be with us until we either die or Christ returns) " For I have the DESIRE to do what is good, but I cannot carry it out. For what I do is not the good I WANT to do; no, the evil I do not want to do-this I keep on doing. Now, it is no longer I who do it, but it is Sin living in me that does it. " Ok, Take a breath! We are no longer sinners by will, only by nature. We can now go before God and say "hey God I messed up again please fix me! and he will! Paul is laying the groundwork for our nature. he is telling us that we are bound by our sinful nature since birth and are enslaved to it. We cannot escape it. We desire to do what pleases ourself rather than what pleases God. Scripture tells us that men love the darkness and hate the light. Unless something changes inside of us, we cannot do good.

    Think of abortion... Can we really ever change someone's mind on a subject like this? Maybe, but we can never chage their hearts. God, speaking through Ezekiel promises us that for those who believe on Him, he will take away their hearts of stone and give them hearts of flesh. Man's hearts are hardened by sin. Only God can come in and remove that hardness and give us hearts that are soft and tender towards God and His Word. We cannot change a single mind towards prolife until we first change their hearts towards Jesus Christ. St. Augustine said "I believe in order that I might understand". These are the same thoughts of the Apostle Paul when he scribed these words:

Rom 1:16-18 For I am not ashamed of the gospel of Christ, for it is the power of God unto salvation to everyone who believes, to the Jew first and also to the Greek. (17) For in it the righteousness of God is revealed from faith to faith, as it is written, "The just shall live by faith." (18) For the wrath of God is revealed from Heaven against all ungodliness and unrighteousness of men, who suppress the truth in unrighteousness,

Rom 1:28-31 And even as they did not think fit to have God in their knowledge, God gave them over to a reprobate mind, to do the things not right, (29) being filled with all unrighteousness, fornication, wickedness, covetousness, maliciousness; being full of envy, murder, quarrels, deceit, evil habits, becoming whisperers, (30) backbiters, haters of God, insolent, proud, braggarts, inventors of evil things, disobedient to parents, (31) undiscerning, perfidious, without natural affection, unforgiving, unmerciful;

and again...

1Co 2:14-16 But the natural man does not receive the things of the Spirit of God, for they are foolishness to him; neither can he know them , because they are spiritually discerned. (15) But he who is spiritual judges all things, yet he himself is judged by no one. (16) For who has known the mind of the Lord, that he may instruct Him? But we have the mind of Christ.

The Gospel awakens our dead spirit and enables us to understand. To truly understand...Without the regenerating power of the Holy Spirit, we are darkened in our minds and supress the truth for our own comfort. We deny God and harden our hearts. This is why Paul goes on to say:

"So I find this law at work: When I want to do good, evil is right there beside me." Paul is saying that this nature, once we come to Christ is no longer in you as it once was. He affirms this when he says " For in my inner being I delight in God's law; but I see another law at work in the members of my body, waging war against the law of my mind and making me a prisoner of the law of sin at work within my members. What a wretched man I am! Who will rescue me from this body of death? Thanks be to God-through Jesus Christ our Lord! So then, I myself in my mind am a slave to God's law, but in the sinful nature a slave to the law of sin."

         This is the perfect illustration of why we sin on a daily basis. As Christians we aren't perfect, but we do have a place to go when we mess up. This grace and love is available to all of God's children, all that is required is commitment and love to Christ that he will be our first love and we will obey him in everything we do. We cannot expect to change the hearts of people on abortion or anything else, but we can pray, share the Word, and let God change hearts. In this way, we will glorify God, have a plave to run to for shelter and stand with a clear conscience that what we are doing is correct because God says so and not because it makes us feel warm and fuzzy inside.