Any leader, writer or designer knows that, before getting started, it is necessary to consider where the project ends. The same is true with the Lenten season; I'd like to ask you to consider the end of this season of the church calendar—not Easter, but the Ascension.

All Christians know the answer to the question, “Why did Jesus come?” But most of us haven’t thought much about an equally crucial question: “Why did Jesus leave?” Forty days after the resurrection, why did He leave? I think we need to know the answer to this question as we prepare ourselves during Lent to fully worship the risen Jesus. While the resurrection that we celebrate on Easter gives us hope in God’s victory, the Ascension gives us our mission—building the Kingdom of God—until Jesus’ return.

There is no more dramatic story in all of world than that of Jesus’ resurrection. His death crushed the hopes of Jesus’ followers, but the stunning resurrection shocks and encourages them. We are told that for the next 40 days Jesus continually appeared to them, teaching them about the Kingdom of God. Their sense of anticipation for what might come next must have been growing and building toward a fever pitch. And then it happens: 40 days after His miraculous resurrection, the risen Jesus leads the disciples to a familiar place on the Mount of Olives, He speaks a few words about the promised Holy Spirit, about how the disciples are to be His witnesses to the ends of the earth. And then, as Acts chapter 1 tells us, "He was taken up before their very eyes and a cloud hid him from their sight."

Jesus just left.

The Ascension may be even more astounding than the Resurrection. Jesus just ... leaves? Why?

I want to suggest to you, as followers of Christ, the very mission and purpose of the Church depends on the answers to this question. If we don’t understand why Jesus left, then we will never understand the significance of our lives in Christ today. 

I believe Jesus left because there was something critical He intended for His disciples to do. There was a mission Jesus gave to His Church to accomplish, and Jesus had spent three years preparing His disciples for this critical mission. 

What Jesus prepared His disciples for and what He left us to accomplish is establishing and building the Kingdom of God. 

At the heart of this Kingdom of God—this reign of God—that He spoke of was the Gospel. In Matthew 24, just before His arrest, He said this to His disciples: “This gospel of the kingdom will be preached in the whole world as a testimony to all nations, and then the end will come.”

What did Jesus mean by “the gospel of the kingdom”?

Jesus’ Gospel did not stop at proclamation. He also spoke of compassion and justice, restoring sight to the blind, freeing the captives and the oppressed, promoting economic justice. 

Jesus’ Gospel was spiritual, yes, but it was also social, political and economic—it was practical, relevant, here and now. Jesus described a bigger Gospel, one that began with proclamation and evangelism, but also embraced compassion toward our fellow man and biblical justice.

This whole Gospel demands a total surrender to God’s Kingdom. It requires more than just believing the right things, but also doing the right things. We are called to care for the widow, the orphan, the alien and the stranger—to lift up justice and fight economic disparity; to speak up for the voiceless and hold our governments accountable; to challenge racism and bigotry; to be generous with our money and to live lives of integrity. Jesus called us to wage war against the dark forces in our world and these things would be the assault weapons of God’s advancing Kingdom.

Every follower of Christ is called to love this world that Jesus died for, and we are to carry this Gospel—the whole Gospel—to all the nations. As we prepare to worship the risen Lord this Easter, let’s also prepare for the mission Jesus gave to us.

(Want to try something different this Lent? For ways to put sacrifice into action now, check out Relentless Acts of Sacrifice with World Vision ACT:S.)

Richard Stearns is the president of World Vision, U.S., and author of The Hole in Our Gospel, published by Thomas Nelson.