We must also note that the book of Luke isn’t the only place we see this idea. In the book of John, Jesus says, “You search the Scriptures because you think that in them you have eternal life; and it is they that bear witness about me, yet you refuse to come to me that you may have life” (John 5:39-40, emphasis added). Again, Jesus tells us that the Old Testament bears witness to him. Therefore, according to Jesus, the Gospel is the key to unlock a fuller understanding of the Bible.
How does this relate to preaching? If the purpose of a sermon is to open a passage of Scripture and faithfully preach the text to your audience, and the best way to interpret Scripture is through the Gospel—as Jesus said—then to preach a passage of Scripture without the Gospel is a failure to faithfully interpret Scripture.
This is why pastor and author Tim Keller writes, “You can’t properly preach any text—putting it into its rightful place in the whole Bible—unless you show how its themes find their fulfillment in the person of Christ.”1 Christ is the key to proper interpretation. Old Testament scholar Graeme Goldsworthy says this about interpreting the Old Testament: “We do not start at Genesis 1 and work our way forward until we discover where it is all leading. Rather we first come to Christ, and he directs us to study the Old Testament in the light of the gospel. The gospel will interpret the Old Testament by showing us its goal and meaning.”2
For example, the Gospel shows that God’s command for Abraham to sacrifice his son Isaac, only to provide a different sacrifice in the final moment, was not some cruel test. It was a foreshadowing of how God would one day sacrifice his son Jesus in our place (Gen 22:1-9). The Gospel shows that the Passover (the angel of death passing over the homes of the Israelite people in Egypt that covered their doorpost with a lamb’s blood, and killing the first born son of all the Egyptians) was not a one-time miracle. It was a symbol of how God would one day pass over exacting judgment on his people, because of the blood of the Lamb, Jesus, shed for us. To preach passages like these without explaining the Gospel connection misses the entire point.
The Old Testament points forward to the cross, and the New Testament points back to the cross. Therefore, in order to faithfully preach the Word of God, we must always look through the lens of the Gospel.
The Gospel Was the Primary Theme of the Sermons of the Early Church.
The Gospel clearly played the starring role in the preaching of the early church. In the book of Acts, we see Christianity spread like wildfire from a group of 120 followers of Jesus to thousands of devoted followers. How did this young movement spread? It spread through preaching. What was the resounding message of these sermons? In short: the Gospel. This is obvious by simply reading through any mention of preaching in the book of Acts.
The first sermon recorded in Acts is on the day of Pentecost. The Holy Spirit descended upon the disciples, a crowd gathered and Peter seized the opportunity to preach the Gospel (Acts 2:36-38). This was just the beginning. Although not exhaustive, consider the following list of examples:
• Peter and John get interrogated by religious leaders who were “greatly annoyed because they were teaching the people and proclaiming in Jesus the resurrection from the dead” (Acts 4:2, emphasis added).
• After the apostles were released from prison with a beating and a warning never to preach about Jesus again, we read this: “And every day, in the temple and from house to house, they did not cease teaching and preaching that the Christ is Jesus” (Acts 5:42, emphasis added).
• “Philip went down to the city of Samaria and proclaimed to them the Christ” (Acts 8:5, emphasis added).
• “Now when they had testified and spoken the word of the Lord, they returned to Jerusalem, preaching the gospel to many villages of the Samaritans” (Acts 8:25, emphasis added).
• Paul is converted to Christianity, “and immediately he proclaimed Jesus in the synagogues, saying, ‘He is the Son of God’” (Acts 9:20, emphasis added).
• Peter declared, “And he [Jesus] commanded us to preach to the people and to testify that he is the one appointed by God to be judge of the living and the dead” (Acts 10:42, emphasis added).
• “But there were some of them, men of Cyprus and Cyrene, who on coming to Antioch spoke to the Hellenists also, preaching the Lord Jesus” (Acts 11:20, emphasis added).
• “Peter stood up and said to them, ‘Brothers, you know that in the early days God made a choice among you, that by my mouth the Gentiles should hear the word of the gospel and believe’” (Acts 15:7, emphasis added).
• When Paul was in Athens, “Some of the Epicurean and Stoic philosophers also conversed with him. And some said, ‘What does this babbler wish to say?’ Others said, ‘He seems to be a preacher of foreign divinities’—because he was preaching Jesus and the resurrection” (Acts 17:18, emphasis added).
• The final sentence in the book of Acts says, “He [Paul] lived there two whole years at his own expense, and welcomed all who came to him, proclaiming the kingdom of God and teaching about the Lord Jesus Christ with all boldness and without hindrance” (Acts 28:30-31, emphasis added).