Context for Paul and Solomon's usage of "heap burning coals on his head."

> Romans 12:20 - "On the contrary: "If your enemy is hungry, feed him; if he is thirsty, give him something to drink. In doing this, you will heap burning coals on his head." > > Proverbs 25:22 - "In doing this, you will heap burning coals on his head, and the LORD will reward you." Do these two verses have the same contextual meaning or are Paul and the author of Proverbs saying different things? And what might the meaning be given their context?