“But all did not obey the gospel. For Isaiah says, Lord, who has believed our message? So faith comes from what is heard, and what is heard comes through the message about Christ.” (Romans 10:16–17 HCSB)

Paul quotes from Isaiah 53.1 here.  The message of the gospel is not obeyed by all, is not believed by all.  The Suffering Servant comes and is punished for our transgressions, but not all believe it.

Faith in Christ comes from hearing.  What is heard (and what must be believed) is the message about Christ.  The message from Isaiah 53, which speaks of Christ:

“But He was pierced because of our transgressions, crushed because of our iniquities; punishment for our peace was on Him, and we are healed by His wounds. We all went astray like sheep; we all have turned to our own way; and the LORD has punished Him for the iniquity of us all.”(Isaiah 53:5–6 HCSB)

 The message of the gospel is a message about Christ.  We are sinners.  He is sinless.  We deserve punishment.  He was punished in our place.