Romans 10:14-15

Paul turned from the responsibility to believe to the responsibility of the believer. "They" refers to the lost, particularly Israelites. Paul presented the logical sequence in a lost person’s coming to faith in Jesus Christ in reverse order here. Faith depends on knowledge of facts. Someone has to proclaim these facts for others to know about them. "A preacher" (NASB) unfortunately implies an ordained minister, but Paul meant "someone preaching" (NIV), someone proclaiming.

Being sent (Romans 10:15) suggests that those heralding the gospel operate under orders from a higher authority. This description also implies that that authority has given them their message. God has sent every Christian to proclaim the gospel to the lost (Matthew 28:19-20; John 20:21). Unfortunately many Christians are waiting for some special calling from God to go. They do not realize that God has already sent them. Where we go and to what segments of humanity we proclaim the gospel are secondary issues. If we get active proclaiming the gospel, God will direct us where He wants to use us (Psalms 37:23).

As is clear from Paul’s quotation of Isaiah 52:7, the message is one of good news that brings joy to those who accept it. "How beautiful are the feet" is a figurative way of expressing gratitude for the obedience of the messengers who have brought good news. The context of Isaiah’s words was the announcement of God’s favor in restoring Jerusalem following the Babylonian captivity.