What Is the Difference Between the Old and New Testaments?
What Is the Difference Between the Old and New Testaments?
The Bible is divided into two major sections, but they are not two competing stories. The Old Testament prepares the way for Christ, and the New Testament shows how God’s promises find their fulfillment in Him.
Open almost any Christian Bible and you will find a page somewhere in the middle marked “The New Testament.” Everything before it is called the Old Testament. Everything after it is the New Testament.
That can make the Bible sound like two separate books.
The first seems filled with creation, Israel, laws, sacrifices, kings, prophets, and wars.
Then the New Testament begins with Jesus, followed by the apostles, the early church, and letters explaining Christian faith.
So what happened?
Are the Old and New Testaments two different religious systems, or are they parts of one larger story?
The Bible tells one unfolding story: creation, fall, promise, redemption, and ultimately the restoration of all things through Jesus Christ.
First, What Does “Testament” Mean?
The word testament is closely connected with the biblical idea of a covenant.
A covenant is a binding relationship established through promises and commitments.
Throughout Scripture, God enters into covenant relationships with His people.
The Old and New Testaments are named around the biblical idea of covenant— God’s relationship with His people and His unfolding plan of redemption.
The Basic Difference
Promise and Preparation
Creation, humanity’s fall, God’s covenant promises, Israel, the Law, sacrifices, kings, prophets, and the growing expectation that God would send a Redeemer.
Fulfillment and Proclamation
Jesus arrives, fulfills God’s promises, dies for sin, rises from the dead, establishes the new covenant, sends His followers into the world, and promises to return.
The Old Testament points forward. The New Testament announces: the One we were waiting for has come.
They Are One Story, Not Two
One of the biggest mistakes we can make when reading the Bible is treating the Old Testament as though it were an unrelated book that Christianity eventually replaced.
Jesus did not arrive disconnected from everything before Him.
His story grows directly from the Old Testament story.
“These are the very Scriptures that testify about me.”
John 5:39
When Jesus spoke of “the Scriptures,” He was speaking about what Christians now call the Old Testament.
You cannot fully understand Jesus without the Old Testament, and you cannot fully understand where the Old Testament is going without Jesus.
The Story Begins With Creation
The Bible begins not with Israel but with the whole human race.
“In the beginning God created the heavens and the earth.”
Genesis 1:1
God creates a good world.
Humanity is made in God’s image.
Human beings are created for relationship with God, one another, and creation itself.
Then sin enters the story.
Humanity rebels against God, and the consequences spread:
Sin
Shame
Conflict
Suffering
Separation
Death
Much of the rest of the Bible answers one enormous question:
What will God do about what has gone wrong with His creation?
God Begins a Covenant With Abraham
God calls a man named Abraham and makes remarkable promises to him.
“All peoples on earth will be blessed through you.”
Genesis 12:3
Abraham’s descendants become the people of Israel.
But God’s purpose was never simply to bless one ethnic group while forgetting everyone else.
Israel was chosen as part of God’s larger purpose to bring blessing to the nations.
Then Comes the Covenant Through Moses
God rescues Israel from slavery in Egypt and brings them to Mount Sinai.
There He gives them His Law.
“You will be for me a kingdom of priests and a holy nation.”
Exodus 19:6
The Law shaped Israel’s:
Worship
Justice
Community
Morality
Priesthood
Sacrifices
The Law revealed God’s holiness and showed Israel how God’s covenant people were called to live.
But the Law Also Revealed a Deeper Problem
Israel had God’s commandments, but commandments alone could not change the human heart.
Israel repeatedly failed.
But so does everyone else.
“There is no one righteous, not even one.”
Romans 3:10
The problem was never merely:
“Human beings need better rules.”
The deeper problem was:
Human beings need changed hearts.
Why Are There So Many Sacrifices in the Old Testament?
This is one of the places where modern readers can become confused.
The Old Testament contains an extensive system of sacrifices.
These sacrifices taught Israel several important truths:
God Is Holy
Sin Is Serious
Forgiveness Is Costly
God Provides Atonement
But the sacrifices were never the end of the story.
“It is impossible for the blood of bulls and goats to take away sins.”
Hebrews 10:4
The sacrificial system was preparing God’s people to understand something greater that God Himself would provide.
The Old Testament Also Creates Hope for a King
God makes a covenant with King David and promises that his royal line will have lasting significance.
“Your house and your kingdom will endure forever before me; your throne will be established forever.”
2 Samuel 7:16
Over time, the prophets begin describing a coming ruler— a Messiah— through whom God will bring salvation.
The Prophets Begin Looking Forward
Israel repeatedly breaks covenant.
Kings fail.
Priests fail.
The people fail.
Yet the prophets announce that God has not abandoned His purposes.
They begin speaking about something new.
“The days are coming,” declares the Lord, “when I will make a new covenant with the people of Israel and with the people of Judah.”
Jeremiah 31:31
Notice:
The New Testament idea of a “new covenant” begins inside the Old Testament itself.
God Promises More Than New Rules
Through Ezekiel, God promises:
“I will give you a new heart and put a new spirit in you.”
Ezekiel 36:26
Something greater is coming.
A New Covenant
A New Heart
Forgiveness
God’s Spirit
A Coming King
Restoration
And then the Old Testament ends.
The promise remains.
The expectation remains.
The world is still waiting.
Then the New Testament Begins
The opening words of the New Testament are more important than they may initially appear.
“This is the genealogy of Jesus the Messiah the son of David, the son of Abraham.”
Matthew 1:1
Abraham.
David.
Messiah.
Matthew is immediately telling us:
The story has not restarted. The story is continuing.
Jesus Says He Came to Fulfill the Old Testament
“Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them.”
Matthew 5:17
That word— fulfill— is crucial.
Jesus does not simply discard everything that came before.
He brings it toward its intended goal.
Jesus Brings the Old Testament Story Together
Abraham
God’s blessing reaches the nations.
David
Jesus is presented as the promised Messiah and King.
Passover
Jesus gives His life for the rescue of His people.
Sacrificial System
Christ becomes the once-for-all sacrifice for sin.
The Prophets
Jesus inaugurates the promised new covenant.
Temple
God’s presence with humanity is revealed decisively in Christ.
Jesus Announces the New Covenant
At the Last Supper, shortly before His crucifixion, Jesus takes the cup and says:
“This cup is the new covenant in my blood, which is poured out for you.”
Luke 22:20
Jeremiah had promised a new covenant.
Jesus now says that this covenant is being established through His own death.
The dividing line between the old covenant and the new covenant ultimately runs through Jesus Christ and His cross.
The Cross Changes Everything
The sacrificial system pointed toward atonement.
Jesus offers Himself.
“Christ was sacrificed once to take away the sins of many.”
Hebrews 9:28
Christians therefore do not continue sacrificing animals for forgiveness.
The sacrifice toward which those sacrifices pointed has been offered.
The cross is not God abandoning the Old Testament story. It is God bringing that story to its decisive moment.
Does That Mean Christians Ignore the Old Testament Law?
No.
But Christians read the Law through its fulfillment in Jesus and the new covenant.
That distinction matters.
The Law contains commands related to:
Israel’s Worship
Priests, sacrifices, festivals, purity, and sanctuary practices.
Israel’s National Life
Laws governing ancient Israel as a covenant nation.
Moral Life
Commands revealing God’s character and His purposes for human conduct.
Christians have historically differed over precisely how Old Testament laws should be categorized and applied.
But Christians broadly agree that the coming of Christ changes our relationship to the Mosaic covenant.
Why Don’t Christians Follow Israel’s Food and Purity Laws?
This is a common question.
If the Old Testament says certain foods were unclean, why do Christians eat them?
Because the New Testament itself shows that the covenant situation has changed.
“Do not call anything impure that God has made clean.”
Acts 10:15
The distinction between clean and unclean foods served a purpose within Israel’s covenant life.
With Christ and the inclusion of the nations, that covenant marker no longer functions in the same way.
Does the New Testament Get Rid of God’s Moral Standards?
No.
Jesus does not make holiness irrelevant.
In fact, He frequently takes God’s commands deeper into the heart.
Murder is not merely about the outward act.
Jesus addresses anger.
Adultery is not merely about the outward act.
Jesus addresses lust.
“Be perfect, therefore, as your heavenly Father is perfect.”
Matthew 5:48
Grace does not mean that holiness no longer matters. Grace changes the foundation from which holiness is pursued.
Were People in the Old Testament Saved Differently?
It can sometimes sound as though the Bible teaches two methods of salvation:
Earn Salvation by Keeping the Law
Be good enough, obey enough rules, and God will accept you.
Receive Salvation by Grace
Jesus replaces the old system with a completely different idea.
But that is too simplistic.
Grace did not begin in Matthew.
Abraham trusted God centuries before Moses.
“Abram believed the Lord, and he credited it to him as righteousness.”
Genesis 15:6
Paul later uses Abraham as an example of justification by faith.
“Abraham believed God, and it was credited to him as righteousness.”
Romans 4:3
Salvation has always depended on God’s grace, received through faith— not human beings making themselves good enough for God.
Is the God of the Old Testament Different From Jesus?
This question often arises because people perceive the Old Testament as harsh and judgmental while imagining Jesus as gentle and forgiving.
But that contrast does not survive careful reading.
The Old Testament repeatedly describes God as compassionate and gracious.
“The Lord, the Lord, the compassionate and gracious God, slow to anger, abounding in love and faithfulness.”
Exodus 34:6
And Jesus speaks seriously about sin, justice, and judgment.
The Bible does not present an angry Old Testament God who becomes loving in the New Testament. Both Testaments reveal God’s holiness, justice, mercy, patience, and love.
Jesus Does Give Us the Clearest Revelation of God
There is still something genuinely new when we reach the New Testament.
God has not merely sent another prophet.
God has come near in Jesus Christ.
“The Son is the radiance of God’s glory and the exact representation of his being.”
Hebrews 1:3
The Old Testament reveals God truly.
The New Testament shows the extraordinary fulfillment of God’s revelation in His Son.
What Changes With the Holy Spirit?
The Holy Spirit is active throughout the Old Testament.
But the prophets anticipated a day when God’s Spirit would be poured out in a remarkable new way.
“I will pour out my Spirit on all people.”
Joel 2:28
In Acts, Peter announces that this promise is being fulfilled.
“This is what was spoken by the prophet Joel.”
Acts 2:16
Again, the pattern is:
Promise in the Old Testament. Fulfillment in the New.
What About Israel and the Church?
This is a large theological subject, and Christians have different views about some of the details.
But the New Testament makes one thing unmistakably clear:
through Jesus, the Gospel goes out to the nations.
“There is neither Jew nor Gentile… for you are all one in Christ Jesus.”
Galatians 3:28
This does not mean Israel’s story was a mistake.
It means God’s promise to bless the nations through Abraham is reaching outward through Christ.
So How Should Christians Read the Old Testament?
Not as an obsolete book.
And not as though we were ancient Israelites living under the Mosaic covenant.
We read it as Christian Scripture, asking how each part fits within the Bible’s unfolding story.
Read in Context
Ask what the passage meant in its original setting.
Locate It in the Story
Creation? Abraham? Moses? Kings? Exile? Prophets?
Ask What It Reveals About God
His holiness, justice, mercy, faithfulness, and purposes.
Look Forward
Ask how the passage contributes to the expectation of God’s redemption.
Read Through Christ
Ask how Jesus fulfills or transforms what came before.
Apply Through the New Covenant
Do not simply copy an Old Testament command directly into modern life.
Jesus Himself Taught People to Read the Bible This Way
After His resurrection, Jesus walked with two disciples on the road to Emmaus.
“Beginning with Moses and all the Prophets, he explained to them what was said in all the Scriptures concerning himself.”
Luke 24:27
Imagine that Bible study.
Jesus walks them through the Old Testament and shows them where the story has been heading.
The Old Testament becomes clearer when we see where the story is going. The New Testament becomes richer when we understand where the story came from.
One Bible. One Story. One Savior.
The Bible contains sixty-six books, written across centuries, through many human authors, in different literary forms.
Yet a remarkable story runs through it.
Creation
Fall
Promise
Israel
Jesus
Cross
Resurrection
Church
New Creation
The Bible begins with creation and ends with new creation. Jesus stands at the center of the story that takes us from one to the other.
What Is the Difference Between the Old and New Testaments?
The Old Testament prepares; the New Testament fulfills. The promises and expectations of the Old Testament lead toward Jesus Christ.
The Old Testament establishes the covenant story. We meet Abraham, Israel, Moses, the Law, the sacrificial system, David, and the prophets.
The prophets promise something greater. They anticipate a new covenant, a new heart, God’s Spirit, a coming King, and restoration.
Jesus fulfills the story. He identifies His mission as the fulfillment of the Law and the Prophets.
The cross establishes the new covenant. Jesus offers Himself for sin and brings the sacrificial system toward its fulfillment.
Christians still need the Old Testament. Without it, much of Jesus’ identity and mission becomes difficult to understand.
Christians read the Old Testament through Christ. We recognize where we stand in the biblical story and read earlier covenant commands accordingly.
Both Testaments reveal the same God. His holiness, justice, mercy, faithfulness, and love run throughout Scripture.
Don’t Skip the First Half of the Story
It is possible to read only the New Testament and know many important things about Jesus.
But you will miss much of the depth of who He is.
Why call Him the Lamb of God?
Why does Passover matter?
Why is He called the Son of David?
What is a covenant?
Why does sacrifice matter?
Why does Matthew begin with Abraham?
Why does Revelation end with a restored creation?
The New Testament answers questions the Old Testament taught us to ask.
And when the two are read together, the Bible’s larger story begins to come into focus.
God creates. Humanity rebels. God promises. God pursues. God rescues. Christ comes. Christ dies. Christ rises. And God promises to make all things new.
“Lord Jesus, open my eyes as I read Your Word. Help me understand the story You have been telling from beginning to end. Show me God’s faithfulness in the Old Testament, the fulfillment of His promises in the New, and above all, help me see You more clearly throughout the Scriptures.”
The difference between the Old and New Testaments is not that God abandoned one plan and invented another. The New Testament reveals the fulfillment of the redemption God had been preparing all along.
The promises, covenants, sacrifices, kings, prophets, and hopes of the Old Testament ultimately help us understand who Jesus is and what He came to accomplish.
“Everything must be fulfilled that is written about me in the Law of Moses, the Prophets and the Psalms.” Luke 24:44