The Great Gospel Harvest Text: Isaiah 27:12-13
Introduction: Reading Prophecy with New Covenant Eyes
When modern evangelicals come to a passage like this one in Isaiah, they often bring a peculiar set of spectacles with them. They are wearing newspaper-exegesis glasses, tinted with Scofield's notes and the latest headlines from the Middle East. They read of a trumpet, of a gathering of Israel, of exiles from Assyria and Egypt, and they immediately begin to construct elaborate charts about the end times, looking for a future fulfillment that involves the modern secular state of Israel.
But this is to misread the prophets entirely. It is to read the mail of the Old Covenant people of God and to completely miss the glorious postscript added by the Son of God. The New Testament is not an appendix to the Old; it is the key that unlocks its meaning. All the promises of God find their Yes and Amen in Christ Jesus. Therefore, we must read this prophecy not as a roadmap for the twenty-first century, but as a glorious picture of the central work of God in all of history: the gathering of His people through the preaching of the gospel of His Son.
Isaiah is not predicting a future mass airlift of ethnic Jews back to a parcel of land. He is describing the great spiritual harvest that would be inaugurated by the Messiah. This is a prophecy about the Great Commission. It is about the power of the gospel to seek and to save the lost, one by one, from every corner of the globe. The language here is agricultural and martial, harvest and homecoming. It speaks of a divine threshing and a great trumpet blast. These are not descriptions of geopolitical events to be tracked on CNN; they are profound metaphors for the work of salvation in the new covenant age, the age we have been living in for the last two thousand years.
So let us take off the dispensationalist spectacles and put on our Christ-centered, covenantal lenses. When we do, we will see that this is not a passage about a future that is yet to come, but about a glorious reality that is happening right now. God is at work, gathering His people, and He uses the most unlikely means to do it: the foolishness of preaching.
The Text
And it will be in that day, that Yahweh will start His threshing from the flowing stream of the River to the brook of Egypt, and you will be gathered up one by one, O sons of Israel.
And it will be in that day, that a great trumpet will be blown, and those who were perishing in the land of Assyria and who were banished in the land of Egypt will come and worship Yahweh in the holy mountain at Jerusalem.
(Isaiah 27:12-13 LSB)
God's Personal Harvest (v. 12)
We begin with the Lord's great threshing operation.
"And it will be in that day, that Yahweh will start His threshing from the flowing stream of the River to the brook of Egypt, and you will be gathered up one by one, O sons of Israel." (Isaiah 27:12 LSB)
The phrase "in that day" points us to the great day of God's intervention, the dawning of the Messianic era. This is the age of the new covenant, inaugurated by the death and resurrection of Jesus. And what is the characteristic work of this age? It is a great "threshing." A threshing floor is a place of separation. The grain is beaten to separate the valuable kernel from the worthless chaff. This is a picture of God's sovereign, discriminating grace. The preaching of the gospel is God's threshing sledge. It goes out into the whole world, and it has a twofold effect: it saves some and it hardens others. It separates the wheat from the chaff. This is a work of judgment and salvation combined.
And where does this threshing occur? "From the flowing stream of the River to the brook of Egypt." The River is the Euphrates, the eastern boundary of the promised land, and the brook of Egypt is the western boundary. In one sense, this is poetic language for the whole land of Israel. But in the light of the New Testament, we see its greater fulfillment. These boundaries represent the ends of the earth. The gospel harvest is not confined to a particular geography; it extends to every tribe, tongue, and nation. God is threshing the whole world.
But notice the beautiful intimacy of this work: "and you will be gathered up one by one, O sons of Israel." Salvation is not a mass, impersonal event. It is not a nationalistic or ethnic reality. It is intensely personal. God gathers His people individually. The effectual call of the gospel comes to each of the elect, one by one. The Good Shepherd knows His sheep, and He calls them each by name. This demolishes any idea of a salvation that comes through bloodline or national identity. You are not saved because you are a member of a particular race or nation. You are saved when the Spirit of God applies the work of Christ to you, individually, gathering you like a precious stalk of wheat into the Lord's barn. And who are these "sons of Israel"? The Apostle Paul is crystal clear: "For he is not a Jew who is one outwardly... but he is a Jew who is one inwardly; and circumcision is that of the heart" (Romans 2:28-29). The true Israel is the Church of Jesus Christ, composed of believing Jews and Gentiles, gathered one by one into one body.
The Great Gospel Summons (v. 13)
The means by which this individual gathering is accomplished is described in the next verse.
"And it will be in that day, that a great trumpet will be blown, and those who were perishing in the land of Assyria and who were banished in the land of Egypt will come and worship Yahweh in the holy mountain at Jerusalem." (Isaiah 27:13 LSB)
What is this "great trumpet"? In the Old Testament, trumpets were used to summon the assembly for worship, to announce the Jubilee, or to call the people to war. The gospel does all three. The preaching of the Word is the great trumpet blast of the new covenant. It is the announcement of the great Jubilee, where the spiritual debts of God's people are cancelled and the captives are set free. It is a call to worship, summoning God's people to assemble before Him. And it is a declaration of war against the kingdom of darkness.
Jesus Himself picks up this imagery in the Olivet Discourse. He says that the Son of Man will "send His angels with a great sound of a trumpet, and they will gather together His elect from the four winds, from one end of heaven to the other" (Matthew 24:31). Now, many people mistakenly shove this event to the end of time. But Jesus says it will happen within that generation. The "angels" are the messengers, the preachers of the gospel, who are sent out into all the world with the trumpet call of the good news. This is the great gathering that Isaiah is talking about.
And who responds to this call? "Those who were perishing in the land of Assyria and who were banished in the land of Egypt." Assyria and Egypt were the great pagan superpowers, the enemies of God's people, the places of exile and bondage. They are types. They represent the state of all humanity apart from Christ. We are all perishing in spiritual Assyria, the land of proud, militaristic rebellion. We are all banished and enslaved in spiritual Egypt, the land of idolatry and bondage. Whether Jew or Gentile, we are exiles, far from God, perishing in our sins.
But when the trumpet of the gospel sounds, these perishing ones, these banished ones, hear the call and they "come and worship." And where do they come? They come to "worship Yahweh in the holy mountain at Jerusalem." Again, we must not be wooden literalists. The writer to the Hebrews tells us what this holy mountain is. "But you have come to Mount Zion and to the city of the living God, the heavenly Jerusalem... to the general assembly and church of the firstborn who are registered in heaven" (Hebrews 12:22-23). The holy mountain is not a physical hill in the Middle East. It is the Church. It is the place of true worship, where God's people, gathered from the spiritual Assyrias and Egypts of this world, are brought into the presence of the living God. This is the fulfillment. The nations are streaming to the true Zion, the Church of Jesus Christ, to worship the Father in spirit and in truth.
Conclusion: The Harvest is Now
This prophecy from Isaiah is not a dusty relic. It is a living description of the age in which we live. The great threshing is underway. The trumpet of the gospel is sounding forth from churches like this one all over the world. God is still gathering His elect, one by one, from every nation on earth.
The perishing are being rescued. The banished are being brought home. The slaves are being set free. And they are all being brought to the true Jerusalem, the Church, to join the great chorus of worship before the throne of God and of the Lamb. This is the central drama of history. It is not about politics or headlines. It is about the patient, powerful, and personal work of God in building His kingdom.
This means two things for us. First, if you are in Christ, you are a miracle. You are one of those kernels of wheat, threshed from the world. You were perishing in Assyria, banished in Egypt, but you heard the trumpet blast of the gospel, and God in His mercy drew you in. You have been brought to Mount Zion. Your response must be one of unending gratitude and joyful worship. Second, it means we have a job to do. We are the ones who are now tasked with blowing that trumpet. We are the messengers sent out to the ends of the earth. The fields are white for harvest, and God has determined to use our faithful proclamation of His Word to gather His people, one by one, until the very last of His elect is safely in the barn.