Romans 10:14–17: How Faith Comes by Hearing
Paul's chain in Romans 10:14–17 moves from calling to believing to hearing to preaching to being sent. Effective evangelism is not persuasion technique but faithful speech of the good news, trusting God to work through his word.
1 Corinthians 1:17–18: The Cross as Message
Paul does not trace where the cross symbol came from. He treats the cross first as a message to be preached, and says its power rests in God rather than in the speaker's skill.