For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
Caty Wagner
I asked Google this same question and found this answer elsewhere. It's helpful but doesn't answer what I want to know- how do we know what to apply? The bible says to keep your hair neat and tidy, not to wear gold or braids, that if a woman is raped in a city then she should be killed and is going to hell, yet these don't hold true today. How do we choose what we choose? I don't want to hear it's for theologians with PhD's to decide. I want to use my own brain. God intended for all of us to be able to read the Bible.
Colin Wong
Hi Caty. You're absolutely right. God intended us all to be able to read the Bible. We don't need a seminary degree or mastery in Hebrew, Aramaic and Koine Greek to understand God's word.
The long and short of it is this. You have to do your homework to understand the Bible as a whole. God's character and attributes does not change. He is the same loving but holy God from the beginning of time through today and to the end of times. But how He interacts with us changes over time. We thankfully live in a dispensation of grace, which is to say, we are made righteous through Jesus Christ, and we do not need to make annual atonements of animal sacrifice through a Jewish high priest as what they did in the Old Testament.
So how do you know what applies to you or not? The answer lies in where a particular scripture was written. Much of the Old Testament was written by Jews for Jews. For example Leviticus describes the ritualistic practices of worship, offerings, and priesthood. No Christian church practices these today. To be a priest in the Old Testament, you have to be of the tribe of Levi (hence Leviticus). If we enforce this, it would pretty much preclude all Christian ministers, pastors and priests (unless you happen to be Jewish and Levite).
Colin Wong
Ultimately as I've said, you have to do your homework and study the entire Bible as a whole. Seek to get an overview of the entire story, how the Old Testament relates to the New Testament. What is the over-arching narrative that ties the entire story, from Genesis to Revelations?
Here's a few pointers to help you in your journey.
1) Seek to understand the difference between Jews and Gentiles.
2) What was God's relationship to man before the giving of the law (Ten Commandments etc.), after the giving of the law (Jewish nation), and after Christ came to fulfill the law (salvation extended beyond Jews to the world)?
3) What does it mean that Jesus did not come to abolish the law but to fulfill it as written in Matthew 5:17-18?
4) Seek to understand God's heart and Jesus' commandment to us in Matthew 22:36-40. This last pointer is the most important.
Ultimately, if in doubt, just focus on point (4). Does the intent of your heart and actions meet the greatest and second greatest commandment of Jesus? If it does not, then you know its sin, regardless of what you think the Bible says.
Here's an example of how Jesus' commandments is greater and higher than our interpretation of law.
Leviticus 22:22
If a man is found lying with the wife of another man, both of them shall die, the man who lay with the woman, and the woman.
Matthew 5:28
But I say to you that everyone who looks at a woman with lustful intent has already committed adultery with her in his heart.
Thankfully Leviticus 20:13 was written for the Jewish nation, and countries like the US, founded on Christian values, focus on forgiveness and redemption through Jesus Christ. So we do not "stone adulterers". Read John 8:1-10.
Hope this helps.