The distance from the Sun allows for the right amount of light absorption The distance from the sun allows for the right intensity of heat. The gravitational pull of the Sun on the Earth keeps it from straying out into space
The right distance between the sun and the earth allows the right amount of radiation to reach the planet. The earth remains at warm temperatures hence its waters remain largely liquid.
Gravitation pull of the sun maintains the earth in orbit and prevents the planet from flying across space
The stability of the sun as a mid-sized star also allows it to burn stably with mild solar flares hence allowing life to exist stably on earth without bombardment by high cosmic radiation.
