Why His Drashos Burned
Rav Refael Yosef delivered fiery drashos that moved his listeners to improve themselves. His grandson, Rav Chaim Palagi, relates that Rav Refael Yosef once explained that Chazal teach that Ruach Hakodesh rests on one who speaks in public. He therefore stood before his listeners in fear of the Shechinah, and that fear was why he became so inflamed as he spoke.
Source: As related by his grandson, Rav Chaim Palagi