Unreached people groups are, by definition, also unrepentant people groups. They have heard the resounding witness of God’s voice through creation and rejected Him (Ps 19:1-2, Rom 1:18-20). Yet they have not been reached by an ambassador who pleads with them to reconsider and be reconciled to God through the Lord Jesus Christ. (2 Cor 5:20) The presence of a witness of the gospel does not guarantee they will repent, but it offers a compelling opportunity to do so. An important part of what drives this mission is the sobering truth of understanding what will happen if they persist in their obstinacy - refusing to the worship the living God and continuing to bow down instead to idols and created things.
Clearly understanding the biblical testimony concerning the dreadful punishment awaiting those who die apart from faith in Jesus fuels the fire of missionary zeal. We must study it, understand it, believe it, and proclaim it to the nations upon whom the wrath of God even now abides. (Jn. 3:36) This, in turn, places the proper weight on the question of what it is precisely that someone must know in order to be born again. What is absolutely necessary for the miracle of regeneration to take place among those who do not honor the Worthy Lamb?