All of this is explained explicitly and broken down in C.S. Lewis' 'Mere Christianity. In the books he breacks down christianity into morality, belief, behavor, and theology. Rather then regurgitate the entire book i will just recomend it. Also, there is not one single argument that can prove Christianity, not one argument that can prove it, and frankly if there was such an argument countless numbers of people would still fail to believe. It is a religion that is both based in faith and reason. It must have a coexistance of both of these, not just faith and not just reason.
Lewis starts of the first chapter of the book by delving into the issue of some moral structure that humanity lives within. Coincidently, he continues in saying that regardless of the fact that we all no what we should do in terms of right and wrong, we do in fact ignore the Natural Law and do the wrong thing. Moving from stating that there is some moral fiber woven in all human mind, he faces peoples objections and concerns with his theory. He addresses this by giving several options in how to define this moral law. The first option is that moral law and herd instinct are two instincts in conflict, fighting for priority. The second is that moral law is a judge of instinct; it decides what instinct to act on being a herd instinct, self-preservation, etc. The third option is that moral law is simply one of our instincts, right in their with the most primitive, the herd instinct and the gut feeling. From this he segues into the argument that rather then instinct that morality is taught and differs from culture to culture. He goes through this conundrum by stating that while some manners in decency are taught (this explains the cultural differences in morality); however, there remains an underlying framework of morality that exists from birth. This continues in to the beginning of a debate on perspective, and how from one perspective something can be seen as downright evil while from an other the action can be as moral as giving food to the homeless. This idea of perspective continues on and is shown through many other examples and demonstrates that the right thing might not always come up on top. He continues in saying that due to the fact that this natural law exists is a testment to the idea of a creator, a builder of the universe. And in end this leads us back to God, being that creator, and Christianity for finding comfort in this land of “moral law.”
With the opening Lewis puts all world views together, as a collective whole, and then weeds them out until only Christianity remains. He confronts them first with their view of God, if there is a God, and then if their God is above good and evil and if their God was a Pantheistic animator or not. He speaks about the fact that with out light, good, there would be no dark, evil, and how each is just the absence of the other. In the second chapter Lewis introduces the Christianity and water idea, the over simplification of the philosophies that are built around and within the faith. He calls this simplification 'boys' philosophies' due to their child like nature, immaturity, and the fact that they are all too shallow; they fail to support any argument because they are fact that relies on almost total faith and very little logic, a blind Christianity if you will. The fact that Christianity is simple does not stand up to Lewis, for he says that it is complex and can not be explained in such simple means because of the fact that the universe is not standard, ordered, and basically symmetrical. Christianity is then applied with a dualistic approach of ying and yang, yet this is not totally applicable in the sense that good and evil are not equal. He states that badness is merely perversion of good thing, ill means to obtain pleasure, money, power, etc.. So, in doing so he states that dualism can not work because the fact that bad is not original, but a perversion of means to reach a good ends that is undertaken by intelligent creatures. He advances this with an extensive WWIIesq analogy of infiltration of good behind the overwhelming battle lines of evil, which has come to infect the Earth. This is exhibited as Christ, a lone paratrooper sent by God to start a good rebellion in a land cloaked in extraordinary evil. This leads into how did the evil come to exist in this land, and why did God allow it to happen by giving us free will and thusly opening us to evil practices? He took a risk, he wanted us to come to him on our own, and he did not want to keep us closed and single minded. God made the choice to give us a choice; it was a risk to do so, and he did lose a large amount of support in doing so, however it was a risk that he was willing to take. He speaks about how the evil originated with the fall of Satan, and his perversion of us by setting it in our heads that we want to be like God; this is followed by God trying to straighten up the Jews as an example, yet more drastic measures are necessary. This leads back to the paratrooper Jesus, the one sent by God to get us going back in the right track, and if need protect us from ourselves by sacrificing himself. Enters theology, and the difference between different practices within the faith and what Jesus was and why he did it. Lewis takes the stance that Christ was ether God, Satan, or some nut job. He continues in the question of how and why Christ died for us, yet he makes it know that it is irrelevant and that we should concentrate on the fact that he did die for us. He dives into how different Christians view Christ, their individual denominations, how Christ works within them and how they are right. He closes the book by wrapping up the paratrooper analogy, when his great army does have its D-Day, will you be the one who says 'God, man, I was with you the whole time,' or do you want to be the man that he already knew was with him prior to the invasion.
Lewis begins by dividing up morality into three distinct areas. The first is when a problem arises with people around a person, outward conflict, a problem arises inside a person, inward conflict, and when there is no direction in ones life. Problems also arise when a person is overly pragmatic, only concerning themselves with no outward troubles and making sure that everyone is happy, this creates inward conflict by allowing themselves become so deranged inside that they become a terrible person over time. It is stated that one must balance an inner clam, collaboration with other people, and a straight and steady direction in ones life in order to achieve morality. Continuing on, Lewis discusses the four Cardinal virtues, prudence, or a mature common sense, temperance, knowing when and how to control ones self, justice, basic fairness and honesty, and fortitude, courage and ability to stand against adversity. Lewis declares that these virtues must be practiced under ones own will and not just by chance. For example, you stop drinking before you are drunk because the bar catches on fire; this is not a righteous exhibition of temperance, this is not true obedience to God and this will not withstand the test of time. Morality, as he continues, is not rewritten, however it is reinforced by new and more current teachings. The golden rule should not overrule culture or art, for it is not truthful for Christians to take down an offensive painting when others around us let Da Vinci's 'Madonna on the Rocks' continue to hang. We should let art stand in its place just like our art standing currently, not coming under fire with controversy. From this Lewis paints a picture of a perfect Christian society, and it is very commonly recognized as socialism, a world where you work to eat, there is no interest, no obscene amenities, and a land where Christianity is practiced in every trade and walk of life. A good man in Lewis' eyes is one that abides by the golden rule, who knows both good and evil, and he knows that the evil still resides within him. He continues into sexual morality by saying that our sexual instinct has gone wrong by seeing sex as food and that man is a glutton and that it is not found in its place, marriage. This is also demonstrated by people saying that sex is nothing to be ashamed of, but the state of sexual instinct at this time is something to be ashamed of. Continuing on into marriage, Lewis states that marriages is more then love, it is a connection between two halves that make a whole, and this should not be split up by Christians. However, it is not the place of Christians to dictate whether or not other people should be able to get divorced or not. Marriage as love is a pure emotion, and it has no concrete bond that hold the two people together, and in hard times the loose emotional bond can be broken, whereas marriage as a contract can not be broken because it works into the places where love may fail and helps hold the two people together. On the idea of forgiveness Lewis states that we can not be forgiven until we forgive others ourselves. Forgiveness means loving your dearest friend, and also loving your most hated enemy. A person is a sinner, yet he does not hate himself, so intern he hates the sin, however he loves himself and thusly love the sinner. However the sinner must still be punished, and to rightful extent, this includes death if so is the crime, yet when one kills they must do it for punishment or for war, and they should not hate the person or take pleasure in that hate. The greatest sin of all is pride, as described by Lewis, the very sin that cast Satan out of heaven. The moral opposite of this sin is humility, and this tames the competitive spirit in having more then the next man. This pride and greed has brought much strife, yet it is not prideful to accept praise, but it is to hide within pride and enter the center of the religious community. Pride in its most evil form is belittling others to make ones self bigger and ignoring what it may look like from those around. Lewis describes charity as giving to those who have not, put simply. Moreover, charity means biblical love, the acceptance and love of people and giving them forgiveness. Charity is not emotional in the traditional sense; it is being kind to all people regardless of who they are. Hope, as described by Lewis, a positive outlook on the future, both in events in the physical world and what is to come in entering the spiritual world. These spill over into desire in which the Christian only desires things that can exists and can be reached, such is heaven for a Christian. Heaven is not desired or hoped for by a Christian because they can not fathom or understand it. Faith is described in two ways, the first sense is belief, I believe in something so I have faith in something, the second is that even though we attempt at achieving Christian virtues, we will inevitable fail, and we will still be taken back to God. The discovery of good faith is very important, yet it will not let you reach heaven. Instead one must see the light of heaven and God within himself and desire heaven to the extent where goodness is natural within ones self.
that was just a brief synthsis of the first three books
Drivin that Train