Do you hold to the belief that the purpose of the 10 Commandments was solely for instruction? I beg to differ. I believe they served another purpose as well in showing the Israelites, and us, how sinful they and we truly are and why we so desperately need a savior.
In a way, it's like God saying, "You think you are righteous? Consider these 10 Commandments and judge for yourself." Jesus reiterated this sentiment during His sermon on the Mount when He spoke of how to love our neighbors and our God.
13 “You are the salt of the earth; but if the salt loses its flavor, how shall it be seasoned? It is then good for nothing but to be thrown out and trampled underfoot by men."
17 “Do not think that I came to destroy the Law or the Prophets. I did not come to destroy but to fulfill.
18 For assuredly, I say to you, till heaven and earth pass away, one jot or one tittle will by no means pass from the law till all is fulfilled.
19 Whoever therefore breaks one of the least of these commandments, and teaches men so, shall be called least in the kingdom of heaven; but whoever does and teaches them, he shall be called great in the kingdom of heaven.
20 For I say to you, that unless your righteousness exceeds the righteousness of the scribes and Pharisees, you will by no means enter the kingdom of heaven."
21 “You have heard that it was said to those of old, ‘You shall not murder, and whoever murders will be in danger of the judgment.’
22 But I say to you that whoever is angry with his brother without a cause shall be in danger of the judgment. And whoever says to his brother, ‘Raca!’ shall be in danger of the council. But whoever says, ‘You fool!’ shall be in danger of hell fire."
27 “You have heard that it was said to those of old, ‘You shall not commit adultery.’
28 But I say to you that whoever looks at a woman to lust for her has already committed adultery with her in his heart."
31 “Furthermore it has been said, ‘Whoever divorces his wife, let him give her a certificate of divorce.’
32 But I say to you that whoever divorces his wife for any reason except sexual immorality causes her to commit adultery; and whoever marries a woman who is divorced commits adultery."
33 “Again you have heard that it was said to those of old, ‘You shall not swear falsely, but shall perform your oaths to the Lord.’
34 But I say to you, do not swear at all: neither by heaven, for it is God’s throne;
35 nor by the earth, for it is His footstool; nor by Jerusalem, for it is the city of the great King.
36 Nor shall you swear by your head, because you cannot make one hair white or black.
37 But let your ‘Yes’ be ‘Yes,’ and your ‘No,’ ‘No.’ For whatever is more than these is from the evil one."
38 “You have heard that it was said, ‘An eye for an eye and a tooth for a tooth.’
39 But I tell you not to resist an evil person. But whoever slaps you on your right cheek, turn the other to him also.
40 If anyone wants to sue you and take away your tunic, let him have your cloak also.
41 And whoever compels you to go one mile, go with him two.
42 Give to him who asks you, and from him who wants to borrow from you do not turn away."
43 “You have heard that it was said, ‘You shall love your neighbor and hate your enemy.’
44 But I say to you, love your enemies, bless those who curse you, do good to those who hate you, and pray for those who spitefully use you and persecute you,
45 that you may be sons of your Father in heaven; for He makes His sun rise on the evil and on the good, and sends rain on the just and on the unjust."
1 “Take heed that you do not do your charitable deeds before men, to be seen by them. Otherwise you have no reward from your Father in heaven.
2 Therefore, when you do a charitable deed, do not sound a trumpet before you as the hypocrites do in the synagogues and in the streets, that they may have glory from men."
5 “And when you pray, you shall not be like the hypocrites. For they love to pray standing in the synagogues and on the corners of the streets, that they may be seen by men. Assuredly, I say to you, they have their reward.
6 But you, when you pray, go into your room, and when you have shut your door, pray to your Father who is in the secret place; and your Father who sees in secret will reward you openly.
7 And when you pray, do not use vain repetitions as the heathen do. For they think that they will be heard for their many words."
16 “Moreover, when you fast, do not be like the hypocrites, with a sad countenance. For they disfigure their faces that they may appear to men to be fasting. Assuredly, I say to you, they have their reward.
17 But you, when you fast, anoint your head and wash your face,
18 so that you do not appear to men to be fasting, but to your Father who is in the secret place; and your Father who sees in secret will reward you openly."
19 “Do not lay up for yourselves treasures on earth, where moth and rust destroy and where thieves break in and steal;
20 but lay up for yourselves treasures in heaven, where neither moth nor rust destroys and where thieves do not break in and steal.
21 For where your treasure is, there your heart will be also."
24 “No one can serve two masters; for either he will hate the one and love the other, or else he will be loyal to the one and despise the other."
From Jesus' Sermon on the Mount, Matthew 5 and 6, NKJV.
These are very difficult sayings. How many of us can truly say we are capable of fulfilling this? I can't. Imagine walking down the street and being confronted by a mugger. How truly willing would we be to give him/her everything including the clothing off our bodies? Our most likely reaction, if possible, would be to report the incident and have him/her arrested and hold him/her accountable. Or imagine how difficult it would be to love someone that came into your home and raped or murdered one of your children. Most of us would be filled with rage and a desire for vengeance, although we would probably call it justice.