The essential distinction is this:
- Mysticism focuses on our subjective experience of the world.
- Metaphysics focuses on our objective ontological understanding of the world.
The core idea in mysticism is that no expression of language can ever fully capture our subjective experience of the world. The richness and detail of subjective experience transcends description. The best we can ever do is sketch out our experience so that others can compare with their own experience; words become a shaky bridge between the private subjective spaces of different individuals. With that in mind, most mysticisms try to increase our awareness of our own subjective experience and minimize the impact of linguistic constructs, effectively getting us to see the world around us instead of merely talk about it. By direct apperception of this sort, we develop a more intimate connection with the world and more natural relationships to it, relieving many of the conflicts and biases that plague human thought. This is why most mystical traditions have something akin to meditation: a practice of direct unfiltered experience.
Metaphysics, by contrast, is philosophical and intellectual. It attempts to understand the world and our existence in it through language. Metaphysics might investigate what being or knowing or time is; it tries to get at the objective roots of our subjective experience, in order to understand the place of humanity in the cosmos.
Depending on how one approaches it, metaphysics and mysticism are either logical complements or strict antagonists, and the antagonism comes more easily than the complementarity (sad to say).