When someone asks you why as a Christian you look to the Old Testament law to condemn homosexuality but ignore the commands to "not eat pork" or to "not wear polyester" -- what do you say?
A good answer to this objection is to explain the "Tripart Division of the Law". This is the idea that the Old Testament law can be divided into three major sections: (1) The Moral Law, (2) The Judicial Law, (3) The Ceremonial Law. The Moral Law is based on the unchanging character of God. It never changes and it defines what's right and what's wrong (i.e. "Thou Shalt Not Murder" and "Thou Shalt Not Steal", etc.) The Judicial Law is simply how the Israelite Government was to govern the people of Israel (i.e. "If someone murders someone, punish them in this way"). The Ceremonial Law is the requirements for maintaining purity in the sacrificial system (i.e. cleanliness laws, diet laws, sacrificial laws, etc).
The idea is, the nation of Israel was designed primarily to bring about Jesus as the Savior of the world. Jesus' entrance then fulfilled the judicial law. Jesus is also the "lamb of God" who was "sacrificed" for the sins of the world. This then fulfills the ceremonial law as well. Jesus also fulfills the moral law by being totally righteous - and anyone who puts their trust in Him gain his righteous standing before God. But anyone who does not put their trust in Him are judged by their own righteousness against the Moral Law of God. As Christians, we look to the Moral Law not to save us from our sin, but to show us how we can better worship God in obedience to Him through our daily life. Therefore, Christians should seek to keep the Moral Law of the Old Testament as an expression of worship to God for the salvation He has already given to us. The entire Law can of course be summed up as “Love the Lord your God with all your heart, with all your soul, and with all your mind." (Matt 22:37) and "Love your neighbor as yourself." (Matt 22:39).
This explanation is helpful, but often we state this division but don't know which laws fit into which category. The following is what I believe to be an accurate division of the Old Testament Law. Bear in mind, this is only my interpretation. There is no place where scripture clearly makes these distinctions.
Also, note that there are some moral laws with an asterisk "*" after them. That is because these moral laws were made for the specific historical context, but the principle remains the same. For example: Exodus 22:26 says not to withhold your neighbor's cloak as collateral. Back then, people usually only had one cloak for cold weather. It would be cruel to keep someone's cloak because they might freeze to death. Today, that is not an issue. But, the principle of not being cruel does apply to us today.
With all that being said, here are the laws, divided into the three categories. I have attached them in a PDF for easier viewing. Read through it and than take a look at the conclusion.
CONCLUSION You may be wondering why the Sabbath command is cited as a ceremonial law and not a civil law. This is due to Jesus justifying breaking the Sabbath through comparing it to other ceremonial laws.
You also may be wondering why some of the ceremonial laws regarding feasts and festivals are grouped together. This is due in part to lack of time on my end as well as the knowledge that all the laws in that section can be grouped together as "ceremonial".