I think the key to passion, to zeal, is gratitude. Or to put it another way, the fuel to motivate is gratitude.
Ray ComfortVast multitudes of professing Christians fit into the category spoken of here. They call Jesus 'Lord,' but they practice lawlessness. They profess faith in Jesus, but have no regard for the divine law.
Ray ComfortComparing Jesus with history's greatest of human leaders is like comparing the sun to a flashlight with no batteries.
Ray Comfort