What’s the Difference Between the Old Testament and the New Testament?

If you’ve ever cracked open a Bible, you’ve probably noticed that it’s split into two parts, or “testaments.” Here’s a super-quick summary of each of them:

• The Old Testament is the story of God’s relationship with the Israelite people, often called the “Old Covenant.” It begins with the creation of the universe, moves through a vast amount of history, and ends with the building of the Second Temple in Jerusalem about 400 years before Jesus.
• The New Testament is the story of the New Covenant through Jesus Christ, God in human form. It covers a much smaller period — less than a hundred years — including Jesus’ life, death, and resurrection, and the first few decades of the church. And it ends with a vision of the new creation to come.

The word “testament” is often said to come from a Greek word meaning “covenant.” That’s not exactly true, but the two terms are related. It actually comes from a Latin word (testamentum) referring to a personal legal document, specifically a will.¹ It’s related to the word “testify” — what a witness does in court.

So you can think of each testament as a “witness” or official account of God’s relationship with his people. But you will also see that each testament is closely related to a covenant.

But why do we have two separate testaments, anyway? How are they related? Does the Old Testament still matter for Christians?

To answer these questions, let’s take a closer look at the two testaments, how they connect to each other, and — yes — why the Old Testament still matters very much to Christians.

Old Testament vs. New Testament at a Glance

	Old Testament	New Testament
Time Period	Creation to 400 BC	4 BC to New Creation
Dates Written	1446–400 BC	45–100 AD
Language	Hebrew (and Aramaic)	Greek
Number of Books	39	27
Number of Authors	Approx. 24-30	12
Primary Genres	Law, Narrative/History, Poetry, Wisdom, Prophecy	Gospel, Letter, Revelation
Major Characters	Adam & Eve, Abraham, Joseph, Moses, David, the Prophets	Jesus, Mary (Jesus’ mother), John the Baptist, Jesus’ disciples (esp. Peter and John), Mary Magdalene, Paul
Major Events	Creation and Fall Covenant with Abraham Exodus from Egypt & Receiving the Law Conquest of Canaan Establishment of Monarchy Building of the Temple Exile & Destruction of the Temple Return from Exile	Birth & Baptism of Jesus Jesus’ Ministry (Healing & Teaching) Last Supper Jesus’ Crucifixion, Resurrection, & Ascension Pentecost Conversion of Saul/Paul John’s Revelation of Jesus’ Return & New Earth
Covenantal Theme	Obedience to Law	Faith in Jesus
Overlapping Themes	Relationship Between God and His People, Love for God and Neighbor, Caring for the Marginalized

What Is the Old Testament?

The Old Testament — often also called the Hebrew Bible — is the account of God creating the world and forming a special covenant (or series of covenants) with the Israelite people. Even setting aside the creation story, it covers thousands of years from God’s first covenant with Abraham, Isaac, and Jacob, through giving the Law to Moses, through blessing David’s kingship, through the division and fall of his kingdom, Israel’s exile in Babylon, and their eventual return.

Because of the amount of time and material it covers, the Old Testament makes up about three-quarters of the entire Bible.

Language, Dates, and Authors of the Old Testament

• Language: The Old Testament is written almost entirely in Hebrew, except for a few short passages in Daniel and Ezra that are written in Aramaic, a later descendant of Hebrew and the language spoken by Jesus and his disciples.
• Dates: The Old Testament begins at the very beginning of time. Though it doesn’t provide dates (there was no unified calendar back then to do so!), scholars have calculated that Abraham lived approximately 2,000 years before Christ, and Moses about 1500 BC. We have better dates for David (roughly 1010-970 BC) and the Exile (586-538 BC).
• Authors: The Old Testament was written by dozens of different people, though scholars disagree widely on how many and how the composition took place. Traditionally, Moses is considered the author of the first five books (known as the Torah or Pentateuch), and most other books are ascribed to the person bearing their name — although aside from the Psalms and most of the prophets, few of the books actually name their author.

Books and Categories of the Old Testament

The Old Testament contains 39 books. In Christian Bibles, they are typically divided into four categories: the Torah/Pentateuch, Narrative or Historical books, Wisdom Literature, and Prophets. The Prophets are further divided into the Major and Minor prophets (that’s not a judgment of importance, it’s just based on how long their books are.)

Although the Torah and Narrative books are mostly chronological, the remaining books are sorted thematically, with the prophets more or less from longest to shortest.

Jewish Bibles are organized somewhat differently: they’re divided into Torah (Law), Nevi’im (Prophets, which include many of the narrative books), and Ketuvim (Writings, which include the wisdom books, Ruth, and the post-exilic books).

BOOKS OF THE OLD TESTAMENT
Pentateuch	Narrative	Wisdom	Major Prophets	Minor Prophets
Genesis	Joshua	Job	Isaiah	Hosea
Exodus	Judges	Psalms	Jeremiah	Joel
Leviticus	Ruth	Proverbs	Lamentations	Amos
Numbers	1 & 2 Samuel	Ecclesiastes	Ezekiel	Obadiah
Deuteronomy	1 & 2 Kings	Song of Songs	Daniel	Jonah
	1 & 2 Chronicles			Micah
	Ezra			Nahum
	Nehemiah			Habakkuk
	Esther			Zephaniah
				Haggai
				Zechariah
				Malachi

Plot Summary and Themes of the Old Testament

As mentioned, the Old Testament takes us through an incredible journey comprising many important events. Here is a very quick overview:

1. Creation and Fall: God creates the world, then humanity. But Adam and Eve disobey God and are exiled from Eden, introducing sin and death into the world. (Genesis 1-3)
2. First Covenant: God forms a close relationship with Abraham, his son Isaac, and his grandson Jacob. (Genesis 12, etc.)
3. Second Covenant, Exodus, and the Promised Land: God forms a second covenant with Moses through the Law and leads his people out of slavery in Egypt, ultimately reclaiming the land he promised them in Canaan. (Exodus through Joshua)
4. Third Covenant, Davidic Kingdom, and Temple: Following a period of increasing descent into sin and chaos, God blesses David to unite and rule over the Israelite people to help them uphold the Law. David’s son Solomon builds an elaborate temple to worship God in Jerusalem. (1 Samuel 16 through 1 Kings 11)
5. Divided Kingdom and Exile: When David dies, his kingdom soon breaks apart and again spirals into ever greater sin and chaos, repeatedly failing to maintain the Law. Finally, God allows Assyria and Babylon to conquer both kingdoms, destroy the temple, and carry the people off into exile. (1 Kings 12 through 2 Kings)
6. Return and Rebuilding the Temple: After 70 years, the king of Persia (who had conquered Babylon) allows the Israelites to return to Jerusalem and rebuild their temple. (Ezra/Nehemiah)

Most of the wisdom writings come from the time of David and Solomon, when the kingdom was flourishing.

Most of the prophets, however, come from the divided kingdom (and a few from during and after the exile). They constantly warn the Israelites to put aside sinful practices such as child sacrifice and oppression of the poor, but aside from a few great kings (such as Hezekiah and Josiah) who try to right their fathers’ wrongs, the prophets warnings to unheeded.

A few of the prophets (e.g., Ezekiel, Daniel) also engage in a genre known as “apocalyptic” or visionary literature. Finally, other prophets (e.g., Isaiah, Malachi) tell the people that someday, a savior (Messiah, “anointed one”) will come to deliver Israel and institute an everlasting reign of peace and justice.

What Is the New Testament?

The New Testament is the story (four versions of the story, in fact) of Jesus Christ, God incarnate as a man, from his birth to his death and resurrection, as well as the first few decades of the church after his ascension to the “right hand of God,” including the early apostles’ explanations of Jesus’ teachings and what he accomplished through the Cross.

Unlike the thousands of years covered by the Old Testament, the New Testament deals with a period of less than 100 years, and makes up only about a quarter of the Bible.

Language, Dates, and Authors of the New Testament

• Language: The New Testament is written entirely in Greek.
• Dates: Scholars now believe that Jesus was born a few years before 0, probably around 4 BC. He was crucified about 30 AD. The book of Acts begins with his ascension (30 AD) and ends with Paul’s imprisonment in Rome, probably around 62 AD. Some of the other books were written later, toward the end of the first century.
• Authors: The New Testament was written by about 12 authors, with the authorship of a few of the books having been disputed among scholars all the way back to the second century AD. The Gospels were presumably each written by the person bearing their name, and Acts was written by Luke. Paul wrote most of the rest of the books, with the exception of those bearing other apostles’ names, and Hebrews, which is anonymous.

Books and Categories of the New Testament

There are 27 books in the New Testament. Four of them are gospels. Acts, as the sequel to Luke, is the only narrative book in the New Testament that is not a gospel. The remaining books are all letters, with Revelation being an epistolary (“epistle” = letter) account of John’s visions “revealed” by God (or an angel of God).

The letters are often divided into those written by Paul and the “general” epistles by everyone else. As with the Old Testament prophets, they aren’t organized chronologically, but more or less by length, longest to shortest.

BOOKS OF THE NEW TESTAMENT
Gospels & Acts	Paul’s Letters	General Epistles & Revelation
Matthew	Romans	Hebrews
Mark	1 & 2 Corinthians	James
Luke	Galatians	1 & 2 Peter
John	Ephesians	1, 2, & 3 John
Acts	Philippians	Jude
	Colossians	Revelation
	1 & 2 Thessalonians
	1 & 2 Timothy*
	Titus*
	Philemon
*Some scholars question whether these books were written by Paul.

Plot Summary and Themes of the New Testament

As mentioned above, the New Testament mostly follows Jesus’ life, ministry, death, and resurrection, and the acts of his apostles in the following few decades. Here are some of the top events and teachings:

1. Jesus’ Birth, Baptism, and Temptation in the Wilderness: The eternal Word is born to a poor migrant family in Roman-occupied Israel. Much of Jesus’ childhood is left out, leaving us to speculate and wonder. When he comes of age and is ready to begin his ministry, he first is baptized by his cousin John in the Jordan River, and then spends 40 days praying alone in the desert. (Matthew 1-4, Luke 1-4, Mark 1, John 1)
2. Sermon on the Mount: Often considered Jesus’ most important ethical lesson, it includes teachings on how to interpret the Law, how to pray, and the danger of hypocrisy as people of faith. (Matthew 5-7, Luke 6)
3. Jesus Feeds the 5,000: Jesus performs many miracles scattered throughout the four gospels, but this is the only one that occurs in all of them: though he has only five loaves of bread and two fish, he feeds a crowd of thousands of people until they are full. (Matthew 14, Mark 6, Luke 9, John 6)
4. Parables of Jesus: Jesus’ favorite method of teaching was using parables: short, symbolic stories with an important but often subtle moral lesson. (Luke 12-16, Matthew 13, Mark 4, and scattered throughout)
5. Christ’s Passion and Resurrection: Beginning with the Last Supper, through Jesus’ arrest, trial, crucifixion, and ultimate resurrection, these are the final days of Jesus’ physical presence on Earth and the culmination not only of his own life but of God’s eternal plan for the redemption of humankind. (John 13-20, Matthew 26-28, Mark 14-16, Luke 22-24)
6. Ascension, Pentecost, and the Conversion of Saul: Following his resurrection, Jesus appears to his disciples a final few times to provide comfort and instruction before ascending to heaven. Then he sends the Holy Spirit upon them to consecrate their apostolic missions throughout the world. Later, Jesus appears to a Roman Jew named Saul/Paul, who was persecuting his followers but would go on to become his most important apostle. (Acts 1-2, 9)

The book of Acts follows the disciples, especially Peter and Paul, as they spread the Good News (gospel) of Jesus Christ throughout the Roman empire and beyond.

As the message spread and the church grew, they had to deal with many questions of interpretation. Should Jewish followers of Jesus continue to practice the Law? What about non-Jewish converts — should they follow it? Who is welcome in God’s kingdom? What exactly did the Cross accomplish?

The remainder of the New Testament is almost entirely letters sent from Paul and other apostles to churches or occasionally individual recipients to address these sorts of questions. They provide admonishment, exhortation, encouragement, and above all doctrinal clarity to the nascent church.

Finally, in Revelation, John of Patmos (who may or may not be the same apostle John who wrote the gospel and letters) received some astonishing — and quite controversial — visions of Christ’s eventual Second Coming, judgment, and restoration of the world.

How Are the Old and New Testaments Connected?

There are several important ways that the New Testament is connected to the Old Testament, making the Old Testament indispensable reading for Christians wanting to understand Jesus.

• The Old Testament Was Jesus’ Bible: Jesus himself was a Bible teacher who taught constantly from the Scriptures. And remember — in his day the New Testament hadn’t been written yet! The Old Testament was the Bible for Jesus and his disciples, full stop. The New Testament didn’t get added until over a hundred years later.
• Jesus’ Ancestors: Those long genealogies such as the one opening Matthew’s gospel aren’t there just to bore you. They show that Jesus was directly linked to Abraham, Isaac, Jacob, David, and other important Old Testament figures.
• Old Testament Quotes and References: To illustrate the previous point, the New Testament directly quotes the Old Testament over 300 times, and indirectly alludes to it another 500-600 times on top of that. The writers of the New Testament lived and breathed the Old.
• Jesus Fulfilled Old Testament Prophecies and Symbols: Jesus fulfilled hundreds of prophecies from the Old Testament (the exact number varies depending on interpretation). Even aside from those, the Old Testament is positively stuffed with symbols that prefigure and point to Jesus.
• Continuity of God’s Covenantal Plan: Just as God’s covenant through David didn’t supplant his covenant with Moses, the arrival of Jesus didn’t wipe away God’s earlier covenants. The Lord is faithful. Jesus said he came to fulfill rather than abolish the Law. In other words, the New Covenant through Jesus expands and enriches — but doesn’t replace or remove — the Old Covenant.

Should Christians Read the Old Testament?

Yes, absolutely. Just as careful readers will find Jesus showing up everywhere in the Old Testament, every page of the New is chock-full of prophecies, quotes, references, allusions, and stylistic callbacks to the Old Testament.

In short, if you want to know Jesus, you need to read the Old Testament.

FAQ: Settling Common Misconceptions

Q: Did Jesus Abolish the Old Testament Law?

A: No. Jesus came to fulfill, not to abolish the Law. “For truly I tell you, until heaven and earth disappear, not the smallest letter, not the least stroke of a pen, will by any means disappear from the Law until everything is accomplished. Therefore anyone who sets aside one of the least of these commands and teaches others accordingly will be called least in the kingdom of heaven, but whoever practices and teaches these commands will be called great in the kingdom of heaven.” (Matt. 5:18-19 NIV).

Paul and other New Testament authors write extensively about whether and how Christians should interpret and apply the Law in their lives. But one thing is clear: we can’t afford to be ignorant of it.

Q: Is God different in the Old Testament and New Testament?

A: No, the Lord is one (Deut. 6:4). He is faithful, constant, and unchanging. Some have misinterpreted God in the Old Testament to be a different, lesser god than in the New Testament — a belief known as Marcionism after the teacher who propagated it — but this belief was universally condemned as heresy by the early church.

Q: What Old Testament prophecies did Jesus fulfill?

A: Jesus fulfilled hundreds of Old Testament prophecies. Though the exact number varies depending on your interpretation, the number is typically over 300. The NIV Application Bible boils them down to 38 core prophecies. Here are a few examples:

MESSIANIC PROPHECIES AND THEIR FULFILLMENT
Summary	Old Testament Prophecy	New Testament Fulfillment
Will Descend From the Tribe of Judah	Genesis 49:10	Luke 3:23, 33
Place of Birth	Micah 5:2	Matthew 2:1
His Triumphal Entry	Zechariah 9:9	John 12:13-14
Suffered Vicariously	Isaiah 53:4-5	Matthew 8:16-17
Hands and Feet Pierced	Psalm 22:16	John 20:27
Source: NIV Application Bible, Zondervan, 2025.

Conclusion: Two Testaments, One Story

Ultimately, the reason the Bible is split into two testaments is more about context than content. The Old Testament was written in Hebrew hundreds of years before Christ, while the New Testament was written in Greek in the decades after his coming. But they are both part of the same larger story.

Like your favorite series, this story can be broken into different parts. But each part can only be truly understood if you know the whole thing.

Unlike your favorite series, though, the Bible is a living story. And every time you open it, you participate in the story God is telling, the “greatest story ever told” — the story of God’s relationship with his people.

Go deeper into the living story of the Bible with Bible Gateway Plus. You’ll get instant access to dozens of trusted study tools and commentaries that can help you explore genre, context, and meaning with greater depth and clarity. (Indeed — it’s where I did most of my research for this article.) Get started with a free trial today!

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1. The Latin testamentum was used to translate the Greek word διαθήκη (diatheke), which had more of the meaning we now think of as “covenant.” ↩︎