“16 However, they did not all heed the good news; for Isaiah says, ‘LORD, WHO HAS BELIEVED OUR REPORT?‘” Romans 10:16
“Heed” means obey. “Good News” is the Greek word for Gospel. Paul takes Isaiah’s observational question, “who has believed our report” to mean, and Paul was Holy Spirit inspired, “obey the Gospel”. Isaiah was asking in Old Testament terms, “Who has obeyed our Gospel.” See, the Gospel not only to be believed. It is to be obeyed. The Gospel is a transformational message. The Gospel calls for repentance. The Gospel calls for sinners to turn from the darkness they have lived in, to living in the light of truth. God defines the walk. God defines the new life.
When a man believes in Jesus Christ, the only begotten Son of God, who gave His life for us, he walks a different life. He gets baptized (Romans 6:3-5) and dies to self to live to righteousness. When a man is not obedient to Jesus, he has been misled or is rebellious and is still lost, see 2 Thess 1:8; 1 Pt. 4:17.
If we believe, Jesus is Lord and Master who we obey. Obey His Gospel. Obedience clearly is not an anti-grace, anti-Gospel word. Obedience is integral to the faith response. If we are not obedient, we do not yet believe. Belief alone is not belief. The belief that saves is obedient faith, Romans 1:5; 16:26.