Our Bibles are composed of two major parts, an Old Testament and a New Testament. A testament is a will or a covenant. We still use the word today when we speak of a person’s “last will and testament.” These names indicate that the Bible is composed of two wills of God — an old will and a new will.
The change in wills is discussed at length in the letter to the Hebrews. In Hebrews 1:1-2, the author says, “God, after He spoke long ago to the fathers in the prophets in many portions and in many ways, in these last days has spoken to us in His Son, whom He appointed heir of all things, through whom also He made the world.” God has changed the manner in which he directs his people. This change was foretold in Jeremiah 31:31-34: ““Behold, days are coming,” declares the LORD, “when I will make a new covenant with the house of Israel and with the house of Judah, not like the covenant which I made with their fathers in the day I took them by the hand to bring them out of the land of Egypt, My covenant which they broke, although I was a husband to them,” declares the LORD. “But this is the covenant which I will make with the house of Israel after those days,” declares the LORD, “I will put My law within them and on their heart I will write it; and I will be their God, and they shall be My people. They will not teach again, each man his neighbor and each man his brother, saying, ‘Know the LORD,’ for they will all know Me, from the least of them to the greatest of them,” declares the LORD, “for I will forgive their iniquity, and their sin I will remember no more.”” Notice that God said the covenant (or testament) would be different from the law given at Mount Sinai. Why would God change his law? Did he change his mind? No! Rather, the change in the law was planned from the very beginning. Before the world was created, God planned to send his Son and that through Jesus we would obtain salvation (1 Pet 1:19-20 ff; 2 Tim 1:9; 2 Thess 2: 13-14). Such a salvation through Jesus Christ could not take place under the law given by Moses.
The Hebrew writer lists several proofs that the covenant between man and God had changed.
There Was a Change in the Priesthood
The author of Hebrews proves that Jesus is now our High Priest (Heb 5:1-10). However, Jesus was not a descendant of Aaron — he was not even of the tribe of Levi. Rather, we find that the order of Aaron was not meant to be permanent (Heb 7:11). Hence, a change in the order implies there was a change in the Law (Heb 7:12-17). Suppose for a moment that the Law of Moses was still in effect. We would be forced to say that Jesus violated the law when he became our High Priest. However, no violation of the law has occurred because there is a new law in effect.
There Was a Change in the Covenant
There was a problem with the Old Testament__the people did not keep it. There was nothing wrong the Old Law itself, but it did create a dilemma. The law defined what sin was, but it brought no relief from sin. It could only offer a future hope of salvation (Rom 7:7-13). The law bound sin to men, but Christ freed us from sin (Gal 4:21-31 cf; 5:1-4).
There Was a Change in Sacrifices
The Old Law had yearly sacrifices which could not free us from sin. The New Law had a single sacrifice that did free us from sin (Heb 9:16-28 cf; 10:1-8).
Jesus Fulfilled the Law (Matthew 5:17-18)
In other words, He brought it to its completion (Romans 10:4). Before Christ, no one could perfectly keep the law, but Jesus proved that it was possible to keep the law. Jesus showed that God’s law was good, it was man who was the sinner.
When Did This Change Take Place?
Paul said that the Old Law was nailed to the cross (Col 2:14). In Ephesians 2:15, we are told that it was put to death on the cross. Hence, the law changed when Christ died on the cross at Calvary. The author of Hebrews put it this way, “For where a covenant is, there must of necessity be the death of the one who made it. For a covenant is valid only when men are dead, for it is never in force while the one who made it lives.” (Heb 9:16-17). At the acceptance of the Old Law, Moses sprinkled the people with blood (Ex 24:8). The new covenant also began with the shedding of blood — Christ’s death on the cross. Christ’s testament could not come into effect until he, as its author, died.
Though the laws are different, can’t we follow both of them? Does it make any difference which law we turn to, since both laws came from God? God said that he took away the first to establish the second (Heb 10:9). We became dead to the Old Law, so that we might be joined to a New Law (Rom 7:4-6).
We cannot even keep a select portion of the Old Law. The first problem is: How do we determine which portion to keep and which to discard? We know that we are inadequate to make such a decision (Jer 10:23). Besides, it wouldn’t work. If we justify ourselves by one part of the Law, we obligate ourselves to uphold the whole thing (Gal 5:3). It is this very point that caused Paul to argue so strongly against the false teachers of his day. Some Christians, who came from the Jewish faith, were teaching that those who were once Gentiles, must become Jews. However, notice Paul’s strong words, “You have been severed from Christ, you who are seeking to be justified by law; you have fallen from grace.” (Gal 5:4).
Why then is the Old Testament still a part of our Bibles? Romans 15:4 tells us that it was written for our learning — to bring us patience, comfort, and hope. It contains examples for us, so that we will not be caught unaware and make the same mistakes that the Israelites made (1 Cor 10:1-12). In Galatians 3:24-25, we find that the Old Law is our schoolmaster, to bring us to Christ. Now that Christ has come, we are no longer under its dominion. Therefore, we see that we can learn from the examples found in the Old Testament, but when we must determine what God would have us to do today, we must turn to his current will — the New Testament.