Weather (symbol)
The poem utilizes weather symbolism when the speaker uses the phrase “rain or shine” to refer to one’s negative and positive experiences in life. Meteorological phenomena are not under human control. The use of weather imagery thus emphasizes the notion that the vicissitudes of life are determined by supernatural forces, over which humankind has no power, and that while one cannot decide whether it will “rain or shine,” one certainly bears agency over one’s perception of these events.
Heaven (symbol)
The word “Heaven” in “Not Heaven itself upon the past has power” does not refer to the skies in the literal sense, but to the divine. By stating that not even the heavenly powers can manipulate what has already happened, the speaker underscores his argument that there truly isn’t any entity in the universe with the power to go back to the past and change it, and furthermore that regretting or brooding over one’s past is pointless and counterproductive.
