Here’s how it happens:
The “Healer” opens her consciousness to the Infinite, the Universe, Source, God, with the intention of serving humanity. Or maybe just a single human. She fills herself with the Light energy that pours in. She is the empty vessel.
The Infinite overflows into her being, like water pouring out after a dam has broken. The Healer seeks this inflow as greedily as we seek water when thirsty, but the Infinite also requires the Healer. The Healer offers the negative pole in the electrical system, the deficit. The Infinite offers the positive pole, the surfeit. Energy, all up and down the frequency spectrum, from dimension to dimension, from pole to pole, from human to human, flows according to this pattern.
They connect, the Healer and Infinite Intelligence. The power flows, and the charge reverses.