Who has believed what we have heard? And who has the arm of the LORD been revealed to? (53:1; HCSB)
Who would have believed this message that has just been told? This is not a group of preachers complaining that their message has not been heard. Rather, this is the voice of repentant sinners finally seeing the light. The servant will be exalted and sprinkle the nations even though the people will be appalled at his disfigurement. God has just revealed something outstanding, but who will believe it? The arm of the Lord is a picture of God’s military might, as we saw at the beginning of the lesson. God is going to awake on behalf of Israel. God’s power (the arm of the Lord) will be revealed through the servant redeemer. The Gentiles, the nations, will see and understand. But who of Israel will believe what has just been heard? The implication, which is more explicitly stated in the New Testament, is that the Gentiles will believe it but the Jews will not.
36 Jesus said this, then went away and hid from them. 37 Even though He had performed so many signs in their presence, they did not believe in Him. 38 But this was to fulfill the word of Isaiah the prophet, who said: Lord, who has believed our message? And who has the arm of the Lord been revealed to? (John 12:36-38; HCSB)
John tells us that Isaiah’s words were fulfilled when the people rejected Jesus even though they saw so many signs performed. The apostle Paul takes the argument further in his writing to the Romans.
13 For “everyone who calls on the name of the Lord will be saved.” 14 How then will they call on him in whom they have not believed? And how are they to believe in him of whom they have never heard? And how are they to hear without someone preaching? 15 And how are they to preach unless they are sent? As it is written, “How beautiful are the feet of those who preach the good news!” 16 But they have not all obeyed the gospel. For Isaiah says, “Lord, who has believed what he has heard from us?” 17 So faith comes from hearing, and hearing through the word of Christ. (Romans 10:13-17; ESV)
Notice that Paul relates this to the Isaiah prophecy. This was the message revealed about salvation. But not all have obeyed the gospel. Who has not obeyed? Go back to the end of chapter 11 and the beginning of chapter 12 and you will see that it is Israel that has not obeyed, but the Gentiles have attained righteousness by faith. Salvation came through hearing and obey the message about the servant redeemer, prophesied by Isaiah over 700 years earlier.