"Behold, what manner of love the Father has bestowed upon us, that we should be called children of God…" I John 3:1
Man is a sinner. This is evident in the fact that he sins. Just as it is evident that birds are flyers by the fact they fly, and fish swimmers because they swim, so men are sinners because they sin. You have sinned, I have sinned, and the whole race has sinned. We are sinners! But man was not a sinner from the start . No! He was created good. He was created to rule over the earth in righteousness. He was the Earth King. So what happened?...He was corrupted when he disobeyed God.
The virus of sin entered man, infecting him through and through, altering the souls equivalent of the body's DNA, so that every part is reproducing sin. Man has become a sin factory; a very different creature than God created. Now children are born infected and the infection is passed on to their children…The human race is doomed…The disease is terminal.
Man, who was made in God's image, was defiled! This was only possible because he was a creature able to make moral choices and because of this he is a perfect host for this malignant foe. Sin is a parasite. It lives off of the moral nature of man. Whenever man knows he ought to do right, whenever a moral choice is presented to him and the will of God made known, sin becomes alive in him to draw him away to do evil instead. This is the nature of sin which has joined itself to man.
Man, nonetheless, is not an innocent victim. He is held responsible to God for he is still cognitive of right and wrong. He knows what he ought to do but does wrong anyway. He sides with the sin in him. God would have man side with righteousness, with God, even against his own self, but all men have failed in trying to do so. Therefore, God's estimation of the human race is that there is none righteous, no not one! All have fallen short of God's praise.
With each willing act of man in doing wrong, guilt is increased and sin is strengthened. Transgression after transgression in each man's life increases the hold sin has on him until he becomes enslaved, the prisoner of sin, made to work toward his own destruction, to build his own gallows, and to dig his own grave. Even though we live under the shadow of man's first willful sin, under the darkness of Adam's guilt, separated from God as a result, each one of us, as Adam, has also willfully sinned for ourselves, willingly siding with lust against God. We as Adam's children have proved our heredity. Therefore, each man bears his own guilt and will answer to God. Thus we are separated from God because of two things: our guilt, and our sinfull nature which brought on our guilt. Man and God's natures are intrinsically different: man does wrong and God does right. The two shall never be joined. Man's sentence of death is just.
Man then is in need of salvation. He needs salvation from the penalty and consequences of his sins; but he also needs salvation from himself, the sinner. So in God's love, He sent His Son Jesus to die for our sins, to save us from our guilt and just punishment, and to save us from ourselves, from whom we are by birth.
Because man needs a new identity, a fundamental change of his nature, God has made this possible through His Son Jesus Christ. The death and resurrection of Jesus Christ has resulted in a new humanity, a new man. This new man in Christ is without sin and therefore is accepted by God. And just as we received our first nature by birth, we receive the new nature by birth, a rebirth on faith in Christ: "…as many as received Him, to them gave He the right to be children of God, to those that believe on his name; who have been born, not of blood nor of flesh's will nor of man's will but of God." John 1: 12-13. By an act of God, God does for man in a moment of time what man could never do for himself…He is born of God, accepted by God, and embraced by God.
The Holy Spirit quickens - regenerates - that which is deep within man. The new birth of the believer is the rebirth of his spirit. The character of this new life received is the very character that was displayed in Christ. Jesus Christ loved God the Father and submitted to His will in all things as He walked in fellowship with Him. He loved being obedient…He loved being dependent…He loved serving God. The nature of Christ was to look to God for the enabling to do right, to be righteous, to overcome temptation, and to live in love towards others. He did not seek for the ability to do right from within Himself but He turned to His God and Father in meekness and lowliness, expecting to receive the power to do His will. He in humility confessed He could do nothing without the Father. These are the characteristics of the believer's new nature received in his new birth. Like a new born child which instinctively cries to suckle, so does the newborn child of God turn to God to receive all things. Humility and dependence on God is the hallmark of the new nature one receives in Christ.
Up until the resurrection the old nature still remains in us. The believer, however, is to daily put off its influence, through the enabling he receives in His dependence on God through Christ. The old nature with its inclination to sin is not overcome by one's own strength; but as God's children, through humbly abiding and believing in the Father's faithfulness to supply our needs, it is overcome by the power of God.
When we discover, by God's grace, that we are in fact by nature evil, deserving death eternal, we will praise Him for His great love He has shown towards us. We will not be confused when we read the recorded words of our Lord: "Marvel not…you must be born again." John 3:7. But we will know the necessity for our rebirth and we will join with the apostle John exclaiming: "Behold, what manner of love the Father has bestowed upon us, that we should be called children of God…" 1John 3:1