The Mishnah states that pious men and men of good deeds would dance before them with flaming torches in their hands. The Meor Vashemesh on Sukkos writes that the hands symbolize the love and fear that one has for HaShem, so the Mishnah alludes to the idea that the pious people had a tremendous fire burning within them that reflected their love and fear for HaShem, and it was this fire that they danced with before HaShem.