David Platt, author of best-selling book "Radical" and "Follow Me" and senior pastor of the Brooks Hill Church in Birmingham, Alabama, has accepted Wednesday the role as the president of the Southern Baptist Convention's mission arm, International Mission Board (IMB), the world's largest missionary sending organization.

In a personal message, the 36-year-old preacher addressed his 4,500 member congregation in Birmingham, Alabama, and others who received discipleship training through his ministry, Radical, on how God stirred up a passion in him for the unreached.

Platt recounted a trip to Nepal in February, where he witnessed Hindu families burning the bodies of the deceased and scattering their ashes over a sacred river in hope that they would incarnate. The scene came to Platt as a livid imagery of the eternal destiny of those who did not hear the message of Christ.

"Over these past months, God has made it abundantly clear to both Heather [his wife] and me that He is filling in that blank check in our lives and family with a different assignment," said Platt, using the analogy of a blank check to describe how Christians should lay down their lives before God, "with no strings attached, willing to go wherever He leads, give whatever He asks and do whatever He commands in order to make His glory known among the nations."

The election of the IMB board came as an affirmation to Platt as he and his wife have thought about moving to Nepal in order to preach the gospel to the unreached. As president, he reasoned that he would potentially be able to mobilize thousands to reach the unreached, making a significantly much greater impact than if he were to do it alone.

Mobilizing local churches to run after global missions would his objective, said Platt. "Not because I want to leave behind local church, but it is the means that God is going to use for the spread of the gospel to the ends of the earth."

Platt will have to address several challenges that SBC faced, including the ongoing financial crisis in financial support for missionaries, according to trustee and search committee chairman David Uth, pastor of First Baptist Church of Orlando, according to IMB.org

"I think the missionary force, the young people God is calling... represent one of the greatest forces in Christian history right now," Uth said. "While the world is becoming more hostile and anti-Christian in some places, it's as if [young missionaries] passion is growing equally to go to those hard places. That's where we hear young couples saying they want to go, that they want to be radically obedient to what God has called us to do for the nations. The passion is there. How do we equip them and resource them? How do we incorporate strategy that's effective? David is going to address that in a way that's going to bring maximum impact."

With his new role taking effect immediately, Platt asked for prayer for the smooth transitions at the Brook Hills Church and the IMB. He also called for believers to put a "blank check on the table, no strings attached."

"You never know what God's going to do, spent us for your name's sake among the nations," he said. "It is the greatest privilege in the entire world. Not just to be saved by God and His grace, but to be involved by God in His mission in the world."

The IMB has more than 4,800 Southern Baptist International missionaries serving worldwide. The Southern Baptist Convention is America's largest evangelical denomination, claiming more than 40,000 churches with nearly 16 million members.