According to the Bible, the Ten Commandments are laws given by God (Yahweh) to the Jews via Moses, and are considered to be significant in Judaism and Christianity. Skeptics and scholars generally consider the whole Exodus story to be mythical and there probably were no stone tablets of the Ten Commandments. 
It is questionable if Christians should be concerned with the Ten Commandments, since Jesus stated the most significant law for Christianity was the Great Commandment to "love God" and "love thy neighbor". It is likely that it is easier for Christians to follow the Ten Commandments than the Great Commandment.
It is perhaps odd that God didn't provide his basic commandments to Adam and Eve or to Abraham. God choosing that particular person (Moses) and that particular time to deliver the Ten Commandments is illogical and nonsensical. If giving basic ethical laws to Adam and Eve was unnecessary, it was probably also unnecessary to provide them to Moses.
The Ten Commandments have three different versions in the Old Testament:
- Exodus 20:1-17 is the most widely known
- Deuteronomy 5:6-21 is quite similar to the Exodus 20 version
- Exodus 34:12-26 is significantly different and the only version the Bible refers to as the Ten Commandments Exodus 34:28 .
Ethical Decalogue (Exodus 20)
The biblical history of the Ten Commandments begins with a show of smoke, thunder, and lightening as God offers the Israelite a covenant. Follow my rule, he sad, and I'll give you a homeland in Canaan and drive out the present inhabitants. He then announced a set of ten commandments, the content of which appears in Exodus 20:1-17 . This constitutes the traditional and most widely known version of the Ten Commandments.
|1st a b||6th|
|Protestant numbering||Catholic numbering||Commandment|
|1st||1st||Thou shalt have no other gods before me.|
|2nd||1st||Thou shalt not make unto thee any graven image, or any likeness of any thing that is in heaven above, or that is in the earth beneath, or that is in the water under the earth. [...]|
|3rd||2nd||Thou shalt not take the name of the LORD thy God in vain; for the LORD will not hold him guiltless that taketh his name in vain.|
|4th||3rd||Remember the sabbath day, to keep it holy. Six days shalt thou labour, and do all thy work: But the seventh day is the sabbath of the LORD thy God: in it thou shalt not do any work, thou, nor thy son, nor thy daughter, thy manservant, nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates [...]|
|5th||4th||Honour thy father and thy mother: that thy days may be long upon the land which the LORD thy God giveth thee.|
|6th||5th||Thou shalt not kill.|
|7th||6th||Thou shalt not commit adultery.|
|8th||7th||Thou shalt not steal.|
|9th||8th||Thou shalt not bear false witness against thy neighbour.|
|10th||9th & 10th||Thou shalt not covet thy neighbour's house, thou shalt not covet thy neighbour's wife, nor his manservant, nor his maidservant, nor his ox, nor his ass, nor any thing that is thy neighbour's.|
They appear in virtually the same form in Deuteronomy 5:6-21 , except for two differences (further explained below). An alternative set of ten commandments were written on stone tablets Exodus 34:12-26 .
Catholics and Protestants use slightly different versions of the Ten Commandments, based partly on different methods of dividing up the verses in Deuteronomy. The Catholic and Lutheran version does not treat as a separate commandment the prohibition against graven images — an obvious problem for the Roman Catholic church which is rife with shrines and statues. To make up for this, Catholics divide verse 21 into two commandments, thus separating the coveting of a wife from the coveting of farm animals. The Protestant versions of the Ten Commandments retain the prohibition against graven images, but it seems to be ignored since statues and other images have proliferated in their churches as well.
Ethical Decalogue (Deuteronomy 5)
The Book of Deuteronomy provides a recap of the same scene and Deuteronomy 5:6-21 sets forth a second version of God's announced commandments. The two sets of commandments are nearly identical; but for two important differences. With regard to remembering the Sabbath, Deuteronomy states that the purpose of the Commandment is to remind Israel that God had liberated the Hebrews from servitude in Egypt. The Exodus version says that the purpose of the Sabbath is to remind Israel that God rested on the seventh day of creation. Another distinction between Exodus and Deuteronomy appears in the last commandment about coveting of other property. Between Exodus 20:17 and Deut. 5:21, Exodus says a neighbor's wife is considered part of the male's household property. In Deuteronomy, she is separate from the household property. Despite thee nearly identical language throughout the two texts, these two differences show disagreement over what was originally supposed to have been inscribed in stone preserved for all to see and hear.
The Bible also disagrees as to when and where the Israelites received the stone tablets. In Exodus, Moses brings the tablets to Israel during the first few months of the Exodus while camped by Mount Sinai. In Deuteronomy, Moses gives them the tablets forty years later, in the vicinity of Mount Horeb at the entraceway to the Promised Land.
Ritual Decalogue (Exodus 34)
Shortly after Moses returning from Mount Sinai and the whole golden calf incident, Moses smashed the stone tablets on the ground out of fury. After that, Exodus 34:12-26 , God directly told Moses to return on top of Mount Sinai, and God would make an identical (Exodus 34:1 ) copy of the original commandments. Moses did as instructed, and returned with the following commandments written on stone tablets:
- Take heed to thyself, lest thou make a covenant with the inhabitants of the land whither thou goest, lest it be for a snare in the midst of thee: But ye shall destroy their altars, break their images, and cut down their groves:
- For thou shalt worship no other god: for the LORD, whose name is Jealous, is a jealous God: Lest thou make a covenant with the inhabitants of the land, and they go a whoring after their gods, and do sacrifice unto their gods, and one call thee, and thou eat of his sacrifice; And thou take of their daughters unto thy sons, and their daughters go a whoring after their gods, and make thy sons go a whoring after their gods.
- Thou shalt make thee no molten gods.
- The feast of unleavened bread shalt thou keep. Seven days thou shalt eat unleavened bread, as I commanded thee, in the time of the month Abib: for in the month Abib thou camest out from Egypt.
- All that openeth the matrix is mine; and every firstling among thy cattle, whether ox or sheep, that is male. But the firstling of an ass thou shalt redeem with a lamb: and if thou redeem him not, then shalt thou break his neck. All the firstborn of thy sons thou shalt redeem. And none shall appear before me empty.
- Six days thou shalt work, but on the seventh day thou shalt rest: in earing time and in harvest thou shalt rest.
- And thou shalt observe the feast of weeks, of the firstfruits of wheat harvest, and the feast of ingathering at the year's end. Thrice in the year shall all your menchildren appear before the LORD God, the God of Israel. For I will cast out the nations before thee, and enlarge thy borders: neither shall any man desire thy land, when thou shalt go up to appear before the LORD thy God thrice in the year.
- Thou shalt not offer the blood of my sacrifice with leaven; neither shall the sacrifice of the feast of the passover be left unto the morning.
- The first of the firstfruits of thy land thou shalt bring unto the house of the LORD thy God.
- Thou shalt not seethe a kid in his mother's milk.
The difference in content is a Biblical contradiction.  This latter version is believed by scholars to predate the traditional Ten Commandments. These above commandments are only time explicitly labelled as "the Ten Commandments" (in Exodus 34:28 ), whereas the better known version is not.
The Hebrew or Greek word translated as “commandment” actually means “word.” So, despite the rather verbose content of the Ten Commandments, originally, there should have been just “Ten Words” on the stone tablets.
When God finished announcing the terms of the covenant, the people were frightened and asked Moses to talk with God on a one-to-one basis and leave them out of it "lest we die." Moses then went up on the mountain to talk to God and they had a long conversation and perhaps more than sixty, depending upon how the sentences are punctuated and divided (the full list appears in Exodus 21:1-23:26 ) The list has the following preamble: "Now these are the judgments which thou shalt set before them" (Exodus 21:1 ).
We don't need to look at the full substance of these judgments, we should note that variations of all the traditional Ten Commandments appear within this larger list but the substance of the text and the sequence of appearance vary significantly from the traditional version.
At the end of the long conversation, "Moses came and told he people of the words of the LORD, ad all the judgments and all the people answered with one voice, and said, All the words which the LORD hath said will we do. And Moses wrote all the words of the LORD..." (Exodus 24:3-4 ). We have now arrived at the first written statement of God's law and thy are not on stone tablets. The passages says that first Moses told the people "all the words of the LORD, and all the judgments." Then the people said they would follow the "words" and Moses then "wrote all the words of the LORD." While Moses first announces "words" and "judgments" the people agree to only the "words" and Moses writes down only the "words." Where are the Judgments?
Do the "words" and "judgments" mean the same thing or does "words" refer to what God announced to the crowd and "judgments" to the long list of commandments given on the mountain? Since the people already had heard God's announcement and it frightened them, it hardly seemed necessary to repeat it, especially since the essence was already contained within the longer list. Did Moses write down just the "words" announced by God to the crowd, just the "judgments" that only Moses heard or both collections? Were "words" and "judgments" interchangeable concepts?
In context, Moses's action followed immediately after the private conversation on the mountain and one would expect his writing to contain the substance of that conversation. But, what we have here is an example of complicated biblical editing reflecting the interaction of two or more separate traditions.
Christ's "Ten" Commandments
Even Christ's version of the commandments is different. In three of the gospels, someone asks Jesus what the commandments are, and they receive three different answers, depending on which gospel is being read - but in all cases, only five or six commandments are given:
- Matthew 19:17-19 : Thou shalt do no murder, Thou shalt not commit adultery, Thou shalt not steal, Thou shalt not bear false witness, Honour thy father and thy mother: and, Thou shalt love thy neighbour as thyself.
- Mark 10:19 : Thou knowest the commandments, Do not commit adultery, Do not kill, Do not steal, Do not bear false witness, Defraud not, Honour thy father and mother.
- Luke 18:20 : Thou knowest the commandments, Do not commit adultery, Do not kill, Do not steal, Do not bear false witness, Honour thy father and thy mother.
No version of the ten commandments says "do not rape", which is a glaring omission from a supposedly perfect law. There is no prohibition against assaulting people, slavery or torture! The commandments do not strictly say "do not lie" because "bearing false witness" only applies in a legal context.
If God wanted people to love thy neighbour, there is no reason that would not be in the ten commandments. Also, the commandments do not explicitly say you must love God!
Questionable relevance to Christians
Although Jesus referenced the Ten Commandments, they seem to be been superseded in Mark 12:29-31 with the new commandments to "love God" and "love thy neighbour". Therefore, the ten commandments are more relevant to Judaism than Christianity.
The Ten Commandments in United States politics
Starting in 1954, the Fraternal Order of Eagles (FOE), with encouragement from movie director Cecil B. DeMille (director of the 1956 movie The Ten Commandments), began producing granite monuments displaying the Ten Commandments. Today, there are 145 such monuments documented in 34 states, plus one in Canada.
The monuments actually display eleven commandments, since they use elements of both the Catholic and Protestant versions. The commandments are not explicitly numbered on the monuments, but the second commandment is about graven images (as in the Protestant version), and the tenth and eleventh commandments treat the different versions of coveting separately (as in the Catholic version).
A common claim by those who believe that America is a Christian nation is that United States law is somehow based on the Ten Commandments. They point primarily to the laws such as "Thou shalt not kill," "Thou shalt not bear false witness," and "Thou shalt not steal" to claim that these are the basis for modern law.
Most of the other commandments have marginal relevance to modern American law, or none at all.
- No other gods before me: Instituting this as a law would violate freedom of religion, as protected by the first amendment.
- No creation of idols: Instituting this as a law would would violate freedom of religion and freedom of speech, both protected by first amendment
- No taking the lord's name in vain: Instituting this law would violate freedom of speech.
- Remember the Sabbath day: Blue laws exist in many states, however, every time these laws have been challenged, they have been found unconstitutional. Certainly there is no federal law demanding observation of the sabbath. Instituting this as a law would violate freedom of religion. Furthermore, which day is the sabbath, friday, saturday, sunday, or one of the other days?
- Honor thy father and mother: With the exception of unruly children laws, which apply only to minors, instituting this as a law would violate freedom of speech.
- Adultery: It is grounds for divorce and alimony, but it is not punished in any way to indicate that it is a real crime. Instituting this law would violate a number of human rights.
- Coveting: Instituting this as a law would violate the right to pursue happiness, and would be contradictory to any capitalist system.
Promoters of the Ten Commandments cherry pick the Bible. In the chapter immediately following the Ten Commandments (Exodus 21 ), God gives various instructions on how to properly conduct slavery, including the rules for selling one's own daughter as a slave. There is no obvious reason why God's instructions in Exodus 20 are moral and should be followed today, but not God's instructions in Exodus 21. This is especially relevant considering that these laws were never called the Ten Commandments, and the real Commandments from Exodus 34 are never advocated.
Even if the laws of the United States were based on the Ten Commandments, it would make it a Jewish country! Laws in the Old Testament only have secondary importance to Christians, who supposedly follow the New Testament as their primary scripture. This is an instance of Christian's selective use of the New Testament.
- The Real History of the Ten Commandments Project at Religious Tolerance
- Which Ten Commandments? at Positive Atheism
- Different Versions of the Ten Commandments at atheism.about.com
- Hang the Commandments - All 30 of Them by Frank Zindler at American Atheists
- The Ten Commandments: Jesus couldn't name them all either at Dwindling in Unbelief
- The Ten Commandments in the Catechism of the Catholic Church