An explosion in a spiritual sense would suggest a revelation of some sort, a welling up from the depths rather than caused by external factors.
Psychological / emotional perspective: A forceful explosion of an emotion – anger, fear or sexual release for instance – can accomplish a cleansing.
A dream may be a safe space in which to accomplish this, the emotion having been suppressed for some time.
Material aspects: An explosion in a dream usually indicates a release of energy in a forceful way, which will allow us to make changes in the way we express ourselves or in the life we live. Apparently destructive, the outcome may be positive in that the debris has to be cleared away.