The difference between the Old Testament and the New Testament is a simple concept, that sadly, is not accurately taught in a lot of churches. Are we saved by grace or are there works involved? What about the Ten Commandments? 2 Timothy 2:15 says “Study to shew thyself approved unto God, a workman that needeth not to be ashamed, rightly dividing the Word of Truth". When a person does not rightly divide the Bible, divisions abound and denominations are formed. Paul wrote about this in 1 Corinthians 1:11-13
“For it hath been declared unto me of you, my brethren, by them which are of the house of Chloe, that there are contentions among you.Now this I say, that every one of you saith, I am of Paul; and I of Apollos; and I of Cephas; and I of Christ. Is Christ divided? was Paul crucified for you? or were ye baptized in the name of Paul?”
By not truly understanding the difference between the Testaments, heresies take place that prevent people from truly coming to Christ.
When reading the Bible, there are two questions that we must ask:
1) What people was this written to?
2) Which dispensation was this written in?
If you read through the entire Old Testament, you will find that there were 613 laws given to the Jews. God chose the Hebrews as His group of people to demonstrate to the world who He is by setting up an intertwined religious and government system (Gen. 12:3, Exodus 19:6). God made it clear that the Law was only for those living in Israel.
God said in Exodus 12:49 and 22:21, that there was to be one law for all peoples residing in Israel and that the people were not to mistreat non-Jews; however, resident aliens in the land did not have the same privileges such as partaking in Passover (Exodus 12:48). Strangers that wanted to become Jews (citizens of Israel) had to circumcise all of the males in the family. Furthermore, Deuteronomy 4:5-9 shows that the gentile nations would turn away from their pagan practices and turn to the one true God of their own accord.
Who was the Law written to? It was written to the Jews, not to the gentiles.
When was the Law written? When God was showing the Jews how to establish their government in their land of Israel.
Understanding the difference between the Testaments is paramount to truly understanding the Bible and especially salvation. The Old Testament was about works and making atonement for sins. The Apostle Paul said in Ephesians 2:8-9 “For by grace are ye saved through faith; and not of yourselves: it is the gift of God: Not of works, lest any man should boast."
We can learn a lot from the Old Testament. We SHOULD read it because all scripture is profitable and God-breathed (2 Timothy 3:16). However, we should always remember that while “the entire Bible is written for us, not every verse is addressed to us or is written about us.” - Matthew McGee