Without the tilted axis and the revolution around the sun, we wouldn't have the four seasons and growing food would be impossible. The tilted axis also allows the earth to have twice as much land area that can be cultivated than if the sun were always over the equator. The earth is positioned at just the right distance from the sun so that we receive exactly the proper amount of heat to support life. Without the ozone layer which protects the earth from solar ultraviolet radiation, all life would be destroyed.
Earth is the only known planet that has water, making life possible.