Even when we were dead in our trespasses, [God] made us alive together with Christ — by grace you have been saved. ( Ephesians 2:5 5 even when we were dead through our trespasses, made us alive together with Christ (by grace have ye been saved), )

The great missionary hope is that when the gospel is preached in the power of the Holy Spirit, God himself does what man cannot do: he creates the faith that saves. The call of God does what the call of man can’t. It raises the dead. It creates spiritual life. It is like the call of Jesus to Lazarus in the tomb, “Come out!” ( John 11:43 43 And when he had thus spoken, he cried with a loud voice, Lazarus, come forth. ).

We can waken someone from sleep with our call, but God’s call can summon into being things that are not ( Romans 4:17 17 (as it is written, A father of many nations have I made thee) before him whom he believed, `even' God, who giveth life to the dead, and calleth the things that are not, as though they were. ). God’s call is irresistible in the sense that it can overcome all resistance. It is infallibly effective according to God’s purpose — so much so that Paul can say, “Those whom [God] called he also justified” ( Romans 8:30 30 and whom he foreordained, them he also called: and whom he called, them he also justified: and whom he justified, them he also glorified. ).

In other words, God’s call is so effectual that it infallibly creates the faith through which a person is justified. All the called are justified. But none is justified without faith ( Romans 5:1 Chapter 5 1 Being therefore justified by faith, we have peace with God through our Lord Jesus Christ; ). So the call of God cannot fail in its intended effect. It irresistibly secures the faith that justifies.

This is what man cannot do. It is impossible. Only God can take out the heart of stone ( Ezekiel 36:26 26 A new heart also will I give you, and a new spirit will I put within you; and I will take away the stony heart out of your flesh, and I will give you a heart of flesh. ). Only God can draw people to the Son ( John 6:44 44 No man can come to me, except the Father that sent me draw him: and I will raise him up in the last day. , 65). Only God can open the heart so that it gives heed to the gospel ( Acts 16:14 14 And a certain woman named Lydia, a seller of purple of the city of Thyatira, one that worshipped God, heard us: whose heart the Lord opened to give heed unto the things which were spoken by Paul. ). Only the Good Shepherd knows his sheep by name.

He calls them and they follow ( John 10:3 3 To him the porter openeth; and the sheep hear his voice: and he calleth his own sheep by name, and leadeth them out. –4, 14). The sovereign grace of God, doing the humanly impossible, is the great missionary hope.