The law of God is contained in the Bible. It started with the first instructions to Adam:
Genisis 2 16 And theLordGod commanded the man, saying, Of every tree of the garden thou mayest freely eat:
17 But of the tree of the knowledge of good and evil, thou shalt not eat of it: for in the day that thou eatest thereof thou shalt surely die. -KJV
When He brought the Israelites out of Egypt, he gave them many more laws. He was establishing for them their religion and their nation. Therefore, He gave them both religious law and civil law. Exodus 21 is an example of the civil law.
This is where this famous verse is contained.
24 Eye for eye, tooth for tooth, hand for hand, foot for foot, - KJV
He was expressing that if someone harmed another in a way that caused the loss of one of these, then that person should suffer the same loss.
Nations are free to establish their own law, and many chose to exhibit more mercy than these original laws. One does wonder at us presuming to know better how to rule ourselves than God Himself. God was making the nation of Israel and example to the nations.
Leviticus, delivered religious law and set up the priesthood. God says to us "be ye Holy, as I am Holy". In Leviticus He sets up the sacrificial system that Christ will one day make complete once and for all. Here is an example from Leviticus:
16 “Don’t gossip. Don’t falsely accuse your neighbor of some crime,[a] for I am Jehovah.
17 “Don’t hate your brother. Rebuke anyone who sins; don’t let him get away with it, or you will be equally guilty. 18 Don’t seek vengeance. Don’t bear a grudge; but love your neighbor as yourself, for I am Jehovah. - TLB
Then there is Deuteronomy, which is a "retelling" of the law that God gave right before they entered the promised land. This is the book that Jesus quoted most often! Here is an example from Chapter 25:
13-15 “In all your transactions you must use accurate scales and honest measurements, so that you will have a long, good life in the land the Lord your God is giving you. 16 All who cheat with unjust weights and measurements are detestable to the Lord your God. - TLB
Please notice two very important truths here: One is that God does not see telling someone something is sin as being opposed to loving them as yourself! The prevalent view today is that to say doing a thing is wrong is unkind. This is opposed to God's Own Word!
The other is, notice the language on cheating measurements, "detestable". Too many are often referencing the fact that God calls homosexuality an abomination like it's the only sin that God hates, despises, finds abominable. The Truth is that God sees all sins all those ways! He is a Holy God and cannot look upon ANY sin. Therefore ALL sins separate us from Him and His fellowship. And that is why He feels so strongly about sin, because He wants to have that relationship with us!
Thankfully, through Christ Jesus, we can have that relationship with God, imperfect as we are!
As to the law, it all stands, it all remains! None of it has ever been "done away with"! It is all still pertinent and all still true! Christ Jesus Himself tells us that in Matthew 5!
17 Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfill.
18 For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.
19 Whosoever therefore shall break one of these least commandments, and shall teach men so, he shall be called the least in the kingdom of heaven: but whosoever shall do and teach them, the same shall be called great in the kingdom of heaven.- KJV
Notice how He said, "to fulfill". Sacrifice was never done away with, but was finally fulfilled by the "complete" sacrifice of Christ on the cross for our sins! His blood shed there washes the sins of those who call upon Him away! The priesthood was never done away with, but was fulfilled because now we have One High Priest and He is in Heaven on the right hand of the Father to intercede for us there!