The Gospel is the pivot of Christian faith for two reasons. Firstly, the Scripture is a portrayal of redemptive history; each book of the Old Testament foreshadows the coming of Christ and the salvation He accomplishes. The first of the Pentateuch, Genesis (Chapter 3), records that God has already prepared salvation through a Man (Christ's incarnation, read more in Nicene Creed) that will triumph over a Snake (Satan, who also represents death - his punishment for rebellion against God). The old covenantal system includes animal sacrifice, which foreshadows the final resolution of forgiveness of sin through Christ's death (hence He is called the Lamb of God in books such as Isaiah and Revelations). The New Testament testifies to how Christ has fulfilled the prophesies in the Old Testament, how people live as a result of the Gospel, and what is to come (the popularly misconceptualised Armageddeon and the New Heaven and New Earth afterwards). There are many other foreshadowings and fulfilment of Scripture that points to the Gospel - Christ's incarnation to come to earth to fulfill God's wrath against our sin on our behalf, and triumphing over Satan and death three days later through resurrection.
As opposed to what some earlier posts have articulated and tried to reconcile between faith and works, it is helpful to understand that humans are of total depravity, of utter sinfulness since the Fall. This is major-ly why we seek and put so much effort to 'do good', to look for philosophies in life or religions that guide us to being better. We don't go around looking for mantras to do bad, because it is inherent in us. It takes much more effort to forgive a person than to yell 'You evil creep!' at him.
A few quotations from the Bible - Ephesians 2:1 we are 'dead in our transgressions and sins', Romans 3:23 'all have sinned and have fall short of the glory of God' and Psalm 53:2-3 'Everyone has turned away' from seeking God, 'there is no one who does good, not even one'. Surely it can't be that our striving to do good, to bring joy to others, sometimes even at our own expense, is discounted all the way to zilch. And this comes to what our definition of 'doing good' is. 'Doing good' is prevalently seen as bringing benefit to others, sometimes even in moral ambiguity (such as white lies, or concealing truth), according to how we perceive it. It is often a compensation of guilt of what one has done wrong -sometimes in anticipation of it- to appease a stricken conscience. As a side statement, Scripture does not attest to the Kantian morality.
As John MacArthur succinctly puts it, what is good is that which is of eternal value, just as God is the absolute measure of standards. What good humanism approves is not seen as good in the eyes of God because it is not done with according to the recognition of God as the Measure of goodness, which is commonly understood as to the glory of God. Because of our total depravity, all is stained, in our motives, in our carrying out of actions. Our sin barricades us from seeking God, who is of utmost holiness, and therefore negates any eternal value a good deed may have. It is only which Christ can break because He has become the firstfruit of Christians by triumphing over death, so that those who believe in the Gospel by triumph over death (the second death: eternal separation from God and eternal anguish and suffering, cf Revelations 20:14-15, 21:8). The natural entailment of such a statement is that no one does good unless He is able to seek God, the only way to Him through which is Christ, as stated familiarly in John 14:6 'I am the way, the truth and the life, no one comes through to the Father except through Me.' I hope this answers an earlier request for a definition of goodness.
Interestingly, it is the 'exclusivity' or absolution that only Christ can save that accounts for:
(1) Why Jesus was seen as an anti-establishment figure during His earthly ministry: that all the good deeds that the Pharisees did, alongside their sinful deeds of pride and discrimination, are legalistic and thus, zilch in the eyes of God.
(2a) Why some convinced atheists or others of the like find that Christianity is 'restricting', or as a fellow classmate stated, a 'sweeping' statement, which is often seen as arrogant and preposterous.
(2b) Why some Christians dilute the absolution of Sola Christus by agreeing, as some fellow classmates have, that Christ or not, living by conscience (which is already tainted and humanistic, as argued earlier) is the 'right' way to afterlife. Ironically, we're going back to the worldly definition of goodness.
(3) Why people think God is so unloving and totally inconsistent with what He promises in John 3:16 'For God so loved the world'. If I may, this is amply expressed (along with suffering) by the Blackeyed Peas, "Since this guy is from above, you have got me, got me questionin', 'Where is the love?' "
Don Carson provides an enlightening exposition on God's love in his book,
The Difficult Doctrine of the Love of God (1999), that the Bible conveys God's love in five different characteristics. They are related, definite but not any should be absolutised and single-dimensionalised into God's love. Two aspects that can be considered when it comes to the popular contention of loving even Hitlers who have accepted Christ and turned 180 degrees are: God's providential love and elective love. Every one is worthy of love, exemplified by the Noahic covenant, where common grace is extended to all. The Noahic covenant in Genesis 9:11 'Never again will all life be cut off by the waters of a flood'. Common grace is that which is freely given to all, God's people or not, as in Matthew 5:45 'He causes His sun to rise on the evil and the good, and sends rain on the righteous and the unrighteous'. I'm totally sure no one can ever deny common grace. I'm really very sure that no one can ever say that God sucks because He's always only sending storms, literally, over his head, but not over his Christian friends. Or that he doesn't know when the sun rises because God only restricted the view of the sun to believers.
God's elective love tells us that God chooses people, not because of any merits/demerits these persons might have to accumulate favour like in popularity contests, but out of love. If you would allow me to use this analogy, why a man ends up with a certain woman as his wife cannot be explained by popularity contests. In non-flings and non-puppy love relationships, a man doesn't change his wife because another girl is more intelligent, or is less impatient, less suspicious. Sure, there may be other girls who display such qualities, but he loves his wife just because he loves his wife, not any merits the wife has earned whatsoever.
This explains why God chooses His people, exemplified by his choice of Jacob over Esau, as in Romans 9:11-13.
'Yet, before the twins were born or had done anything good or bad - in order that God's purpose in election might stand: not by works but by Him who calls...just as it was written: "Jacob I loved, but Esau I hated.'
In accordance with God's providential display of love to all mankind, and to his sovereign choosing of people, it is hard for Christians to love enemies out of own strength, but through the Gospel. As Jerry Bridges writes in
Respectable Sins: Confronting the Sins We Tolerate (2006), one cannot love enemies unless he comes to realisation that no personal offense by another can surmount to one's spiritual debt to God (that Christ carried punishment that was meant for us because of our sinful nature, cf Romans 5:8, Isaiah 53:4-6). It is difficult to love one's enemies, but through what Bridges calls 'dependent responsibility', Christians are able to fulfill this along with training (cf Hebrews 12) as long as he depends on the Lord for this ability and remembers the spiritual debt that was freely forgiven, though dearly paid for by Christ, ie the Gospel.
A recurring idea that I've been putting forth about the Gospel and Christian life is that salvation is only by faith. Christians are justified before God because a confession of both mouth and heart (Romans 10:9) that only through Christ's power of atonement can one be saved from God's wrath over the sin of mankind. Any attempt to 'try' and do things in order to attain even Christian goals are attempts to credit merit and favour to ourselves, and forfeits what Christians have been commanded to do in Proverbs 3:5-6 'Trust in the Lord with all your heart, and lean not on your own understanding; in all your ways acknowledge Him, and He will make your paths straight.' Notice that this doesn't suggest any God's grace and forgiveness as a license to sin, which some early Christians did, and some Christians nowadays still do, sadly. The Bible reproaches strictly against that: 'Shall we go on sinning so that grace may increase? By no means! We died to sin; how can we live in it any longer?' (Romans 6:2).
Regarding the contention over James 2, which is best expressed by v26, "faith without deeds is dead". I find it a rather common misunderstanding to take this portion to mean that works also count in determining whether one is saved. I suppose proponents have mistaken justification for salvation, that Christianity is ironically teaching that one can accredit merit to himself in order to be made righteous by God. As an earlier post has touched on, a change in life, what the apostle Paul calls 'the new self' (Romans 4:22-24) is to do the moral will of God, ie what is stated in the Bible, such as loving one's enemies. James, the 'half-brother' of Jesus, wrote this to reproach nominal, self-professing Christians whose confessions are only in the mouth, but empty in heart, not to propose that if we do good, that will gain points in helping us complete our percentage of how saved we are. Salvation is complete at the time of confession and acceptance in that we do nothing to earn the full process, to 'level up'.