When you eat you take something in and bring it to life in yourself. Air is closely related to the heavens and the great mystery of transcendence. It is unseen and ungraspable, but it is felt. Its power as wind is extraordinary. Winds bring rain and drought, destroy on their own, and generate a certain kind of chaos.
Air shows the sacredness of breath, a life principle, and suggests spirit.
Fire suggests resurrection, which involves a transformation of form without dissolution or the slow process of decay. Flame is a process, a chemical reaction. Life to ash, spread on fields, yields increased life. Water in symbolic terms, suggests the sum of all virtualities and possibilities. In mythology the waters are said to have existed before earth.