What is 'the Law and the Prophets' mentioned in the New Testament?

TL;DR:

The Law and the Prophets is a way to refer to all of the Old Testament. The Law and Prophets find their fulfillment in Jesus.

By the time of Jesus, the Old Testament Scriptures were commonly referred to as "the Law and the Prophets," reflecting their dual focus on divine teachings and prophetic revelations. The third category, the Writings, was categorized under "the Prophets" because all authors of Scripture were regarded as inspired messengers of God. The Law, or Torah, comprises the foundational books Genesis through Deuteronomy, outlining God's commands and the origins of Israel. The Prophets, including historical and prophetic texts, such as Isaiah, Jeremiah, and the Twelve Minor Prophets, foretold future events and pointed towards Jesus as the fulfillment of God’s promises. Today, understanding these Scriptures helps believers interpret God's overarching plan of redemption, culminating in Jesus Christ, who fulfills the Law and the Prophets' prophecies and teachings.

from the old testament

By the time of Jesus, the Old Testament, or Hebrew Scriptures, were often referred to by the shortened phrase "the Law and the Prophets." The third category of the Writings was lumped under the heading "the Prophets" because, by that time, anyone who wrote Scripture was considered to have been a prophet, literally one who speaks forth the word of God.
The Law or Torah consists of the first five books of the Bible, also known as the Pentateuch or the Books of Moses: Genesis, Exodus, Leviticus, Numbers, and Deuteronomy.
The Prophets or Nevi'im includes various books, categorized into two subgroups: former prophets (Joshua, Judges, Samuel (1 & 2 Samuel), and Kings (1 & 2 Kings)) and later prophets (Isaiah, Jeremiah, Ezekiel, and the Twelve (minor prophets) which include: Hosea, Joel, Amos, Obadiah, Jonah, Micah, Nahum, Habakkuk, Zephaniah, Haggai, Zechariah, and Malachi).

from the new testament

When Jesus referred to the Law and the Prophets in Matthew 7:12 and Matthew 22:40, He was referencing the entire collection of Hebrew Scriptures and highlighting an overarching principle throughout the entire biblical text of His time.
When Philip invited his friend Nathanael to follow Jesus, he asserted that Jesus was the Messiah that the Hebrew texts predicted. He said, "We have found him of whom Moses in the Law and also the prophets wrote, Jesus of Nazareth, the son of Joseph" (John 1:45).
In Acts 13:15, Luke documented the practice of synagogues during his time. They would read a portion from the Torah and then a portion called the haftarah from either the Prophets or the Writings and then have a drash, or teaching, expounding upon those texts. The rules of hospitality dictated that if a guest who was qualified to teach was present, the opportunity would be extended to him after the reading. So in Acts 13:15 Luke recorded, "After the reading from the Law and the Prophets, the rulers of the synagogue sent a message to them, saying, 'Brothers, if you have any word of encouragement for the people, say it.'"
Paul, in Romans 3:21, referenced the entire Old Testament and showed how those scriptures point to Jesus. Paul wrote, "But now the righteousness of God has been manifested apart from the law, although the Law and the Prophets bear witness to it—the righteousness of God through faith in Jesus Christ for all who believe" (Romans 3:21–22).
Indeed, the whole Old Testament points to and is fulfilled in Jesus Christ. Jesus, Himself, explained to His disciples after His resurrection, "These are my words that I spoke to you while I was still with you, that everything written about me in the Law of Moses and the Prophets and the Psalms must be fulfilled" (Luke 24:44). Jesus knew and affirmed all three groups of Hebrew Scriptures—the Law, the Prophets, and the Writings—by mentioning "the Law of Moses and the Prophets and the Psalms." He said they all find the goal at which they had been aiming in Him.

implications for today

When we read the Old Testament, we should be looking for the ways in which it points to Jesus. Many say that the New Testament is the Old Testament fulfilled. Another saying is that the Old Testament is the gospel concealed and the New Testament is the gospel revealed. The Old Testament gave many promises and pictures of the coming Messiah, who is Jesus. The New Testament tells us about Jesus and how His work on the cross and His resurrection affect our lives today. The entire Bible is one coherent story of how God provides salvation for fallen humans through His Son, Jesus the Messiah. The Law and the Prophets are an integral portion of that story and are preserved as the books of the Old Testament in our Bibles today.

When we study the Law, which includes the foundational teachings and commands of God, and the Prophets, who spoke forth God's message and often foretold of the coming Messiah, we find a cohesive narrative pointing to Jesus Christ. His life, teachings, and fulfillment of prophecy exemplify the culmination of God's plan for salvation. Practically, this understanding guides believers today in interpreting the Bible, recognizing Jesus as the fulfillment of God's promises, and living out the principles of love, justice, and faithfulness taught throughout the Old Testament. As Jesus affirmed, the entirety of Scripture finds its ultimate meaning and fulfillment in Him.

understand

By Jesus' time, the Old Testament Scriptures were known as "the Law and the Prophets," encompassing all Hebrew Scriptures.
The third category, the Writings, was often grouped under "the Prophets," considering all Scripture authors as prophets of God.
The Law (Torah) consists of Genesis to Deuteronomy, while the Prophets (Nevi'im) include historical and prophetic books, all pointing towards Jesus as their fulfillment.

reflect

How does understanding the Law and the Prophets deepen your understanding of Jesus as the fulfillment of Old Testament prophecies?
In what ways do the teachings of the Law and the messages of the Prophets shape your daily walk with God?
Reflect on Jesus' affirmation of the Law and the Prophets. How does this impact your view of the Bible's unity and purpose and what it reveals about God’s redemptive plan?

engage

By 300 BC Judaism recognized certain writings as sacred Scripture. These were all written and contained on scrolls because the technology of binding pages into a book (called a codex) did not yet exist. This collection of scrolls was categorized into three groups: the Torah (also called the Law of Moses), the Prophets, and the Writings (sometimes called simply "the Psalms" although it contained ten other scrolls besides the book of Psalms). These sacred Scriptures are what constitute the Old Testament today.
How do the Law and the Prophets collectively point towards Jesus as the Messiah, as seen in both Old and New Testament passages?
Discuss the significance of Jesus' statement that the entirety of Scripture finds fulfillment in Him. How does this unify the Old and New Testaments?