Fire in a dream can point in two directions at once -- passion and vitality on one hand, destruction and loss of control on the other, and the tone of the dream usually tells you which. A fire you're tending deliberately often reflects transformation you're choosing, while one raging out of control may name a change that feels like it's happening to you.
Sol and Mars are fiery; the heat of Mars is destructive, that of the Sun answers the vivifying heavenly fire. - William Lilly (1602.-1681.)