In “Toward a Meaningful Life” Rabbi Jacobson quotes the Rebbe (I don’t remember all of the concept but) that the body and soul are like a flame and a candle – Does the fire need the candle? – well without the candle there would be nowhere for the flame to be! – But does the candle need the flame? – well without the flame, there would be no body! – In other words, though it is the nature of fire to try to ascend and the nature of the body to try to descend (as it states “the spirit of man rises upward,” “the spirit of the animal (the body as well) goes downwards”) it is particularly the tension in which they mitigate one another’s drive, that you create a stable light