Thucycides's existing manuscripts date from about 800 AD. and there are 8 manuscripts. The earliest existing copy of Aristotle's Poetics dates from roughly 1100 AD. There are 5 ancient manuscript copies in existence. No one doubts the essential validity of these works.
In contrast, we have two copies of the New Testament which date from 350 A.D. (Codex Vaticanus and Codex Sinaicus), and fragments which date from as early as 110 A.D. The total ancient manuscript copies of New Testament documents is overwhelming -- over 5500 copies. In addition, there are approximately 20,000 ancient sermons and other writings which quote portions of the New Testament -- enough to reconstruct the entire compliation even if no direct writings existed! These ancient copies exist in Greek, Latin, Hebrew, Aramaic, Syriac, Coptic, Russian, and a variety of other languages.
Furthermore, the most recent good translations of the Bible (such as the Nelson New King James Version) use the earliest documents as a basis for translation. In researching these ancient texts, scholars have found that the disagreement between texts widely scattered in geography and time are insignificant and don't affect any major doctrine of Christianity in the least. In fact, the original spelling or wording of less than 4 percent of the Bible is in doubt -- most of which are issues of a single character or two.
From a literary standpoint, the most amazing thing about this passage is the description of Jesus drawing in the dirt. This type of detail added to a story is common today in fiction, for it increases the realism of the passage. But this added detail is never found in fiction before the early eighteen hundreds. The conclusion, then, is that the writer of the gospel was simply describing what actually happened. The story is true.
Blasphemy was a capital crime in the Jewish theocracy, but capital punishment was reserved by the Roman occupying government. After a jurisdictional dispute, eventually Jesus was whipped and cruxcified. (Cruxifiction is death by hanging on a cross until death occurs due to suffication.)
It is recorded that at the time of Jesus's death, there was a darkness across the land. Since this was similar to a solar eclipse, it is natural to assume this. However, there is a problem with this concept -- the Jewish Passover festival was and is always held at the time of the full moon -- two weeks from the possibility of a solar eclipse. (There are some interesting Roman writings which talk of this darkness which apparently covered much of the Empire.) An earthquake also occured at the time of His death. After His death, confirmed by the Roman authorities with a spear, His body was placed in a rock-hewn cave tomb, and a massive boulder rolled in front of the entrance. A guard was placed over the tomb to prevent any theft of the body.
Three days later, (using Jewish methodology of the time) a few women came to embalm the body. To their astonishment, the tomb had been opened. Jesus greeted one of the women and gave her a message for His disciples. Later that evening, He appeared to them at a meeting. He continued to appear to people for about forty days, including one crowd of 500 people, in a variety of places -- eleven appearances are documented. Then, giving some final teachings, "He ascended into the clouds."
Christians believe that God created physical laws to govern the mechanical operation of the Universe. Among these laws are the law of gravity, quantum mechanics, relativity, laws of motion, laws of electromagnetism, and many other laws which we learn about in science classes. If you ignore these laws, bad things happen. For example, pretending that the law of gravity doesn't exist is not smart, especially when you wish to walk out a third story window. Although you will experience an interesting sensation for a second or so, you will soon regret your decision to ignore this physical law created by God.
In addition, Christians believe that God created laws to govern human behavior. In the same way as physical laws, ignoring these behavior laws is hazardous to your health. For example, during the 1980's, many people ignored the law of monogamy, which states that each man and woman should be faithful to one another, and should only have sexual relations with their spouse. For many of these people, they had a very enjoyable time. However, this led to a variety of problems, including death by AIDS after a few years.
Another human behavior law is to not lie. Although many people have lied, all people eventually understand that lying leads to bad consequences, from a tight, worried stomach -- to prison and the loss of close relationships.
These laws of human behavior are stated in detail in the Old Testament. A summary of the most important is known as the Ten Commandments. In the Book of Matthew, they are restated in a more compact form as the Golden Rule: "Do to your neighbor what you would have him do to you."
A man or woman who breaks these laws commits a crime against God, or "sins". God requires a fine be paid for all sins. For some reason we don't fully understand, but was clearly present in all ancient religions, this fine must be a blood sacrifice, the value of which depended upon the man's ability to pay. A poor man might need to sacrifice a dove, a well-off man sacrifice a ram, and a very rich man sacrifice a bull. Payment of this fine, combined with true repentance, puts a man back into fellowship with God.
However, there was a problem. Since the law applies not only to actions, but also to thoughts, it is impossible for any man to avoid sin. Repeatedly, man sins and sins. He may try to pay the penalties, but is so lost in his sin nature that he cannot even keep track of all of his sins. Since God has all eternity to improve someone -- if they'll let him -- the real questions is whether or not a man will trust God enough to let Him improve the man. Will he put his trust in Him? Thus, God provided a final solution to sin.
To pay for all of a man's sins required the sacrifice of something exceedingly valuable. To pay for the sin's of all people, past, present, and future, requires the most valuable thing in the Universe be sacrificed. One man could only sacrifice his most valuable possession -- his life. But God could sacrifice something even more valuable -- His Life.
Christians believe that the death/sacrifice of Jesus Christ, the Son of God -- God Himself -- was the ultimate sacrifice. At the time of His death, Jesus took all the sins of each man upon Himself and was sacrificed to pay the debt of each man.
When Christ arose from the dead, He demonstrated that He had power over life and death -- something that only the Divine Being has. Thus, He demonstrated that His promise of eternal life could be believed.
Isn't that frightening? What if Jesus asks me to do something that will harm me?
Christians believe that Jesus cannot harm you or ask you to be harmed. He is all-knowing, all-powerful, and all-good. Oh, yes, you may be disciplined as a loving parent disciplines a child. But the ultimate purpose is the good of the child. In the same way, Jesus may have you feel pain and anguish over various things. But Christians believe that those pains are the pains of instruction and discipline. In the end, by following Jesus, you will have a much better life -- and eternal life.
Christians believe that all people are initially in a state of rebellion toward God. This is shown by their continual bad behavior.