People are discussing the Law (old testament vs new). I agree with everything C3PX has said, but i thought i'd add something. People who disdain christianity often point to the old testament and it's extreme nature & use it to make fun of an "evil" & mean spirited God, & "hypocritical" Christians who don't follow all the rules in the old testament. C3PX did a great job explaining why we as Christians no longer follow the law, but he didn't really touch on why it was given to us in the first place.
People often dislike christians b/c they go around calling everyone sinners which is "bad". Well, they are accurate in calling everyone (including themselves) sinners, but i think there is a stigma that people attach to that b/c they take it as an insult & don't fully understand what it means. Sin is simply anything that does not conform to God's will, character, or nature. Of course some of these are bad (murder, theft, etc.) but they don't have to be. it could be as simple as God making it clear to you His will is for you to buy an Xbox 360, & you buy a PS3 instead. (silly example, but it makes the point. it's not aligned with God's nature, & therefore sin).
So what's this got to do with the law? Well, God created us to be with him. His companions & family. He WANTS us to be with him. But he also gave us the ability to choose to follow & love him, or to reject him (to sin!!) this is b/c our love is far more worthwhile if it's voluntary. However, because we (the human race) have decided to sin (which began with Adam & Eve, but continues to this day) there's a problem. God cannot and will not allow sin in his presence. So He had to make a way to wash out our sinfulness. That's where Jesus Christ, the Saviour comes in. But why should we accept him? we seem to be ok, decent people right? wrong! Even the tiniest bit of sin will keep you from the presence of God. SOOOooooo.........
We get.... THE LAW!!! & it's a very harsh, unforgiving law. This is not b/c God is mean, or spiteful. The law is so harsh b/c it's built to show us that no matter how hard we try, we can never be sinless & worthy of God's presence under our own power. We need help. We need a Saviour! Thus leading us back to Jesus.
So, the law was in place to show us (after we chose to reject God & sin) that we can never work our way back into His good graces under our own power. Not b/c he doesn't love us, but b/c he can not allow sin in his holy presence. But he does love us!! He loves us so much that he actually died to win us back through Jesus! & when that happened, the law (which was really just a set of rules to get back in God's good graces & wash away sin) was fulfilled & therefore we no longer have to follow it.
HOWEVER, just b/c we are not bound to follow the law does not mean that we cannot learn from it. After all, it was put in place to show us our need for a saviour. Therefore we read it, learn from it, but do not have to follow it.
** Just thought i'd put a note expalining that the law i refer to is the old testament jewish law including, but not limited to, the ten commandments