Power means “power to”, not “power over”, specifically, power to serve people and the rest of creation, not power over them.
The Priest/ess is the channel, not the source, of power.
The more power you spend, the more will flow through you.
Power comes from living in a sacred manner, in right relationship to the people and other beings (including things) around you.
Spiritual power, like physical strength, is best acquired gradually, by regular practice, and will atrophy if not used.
A Priest/ess of the Old Religion withdraws from the world to seek strength and illumination, but then returns to the world to share with others what s/he has learned.
The consecration of a Priest/ess marks the beginning of the real learning, in which the needs of those s/he is serving call forth unsuspected knowledge and force her or him to stretch and grow.
The Priest/ess is always searching for more knowledge: reading, meditating, learning from spiritual leaders of other traditions.
The Priest/ess leads by example, not compulsion (physical, legal or psychological).