Have you ever heard of a Leyden jar? Originally invented in 1745 by Pieter van Musschenbroek at the University of Leiden, the Netherlands, it was a device used to build and store static electricity. You can find the following description (with pictures) at the Sparkmuseum website:
A Leyden jar consists of a glass jar with an outer and inner metal coating covering the bottom and sides nearly to the neck. A brass rod terminating in an external knob passes through a wooden stopper and is connected to the inner coating by a loose chain. When an electrical charge is applied to the external knob, positive and negative charges accumulate from the two metal coatings respectively, but they are unable to discharge due to the glass between them. The result is that the charges will hold each other in equilibrium until a discharge path is provided. Leyden jars were first used to store electricity in experiments, and later as a condenser in early wireless equipment.
Why do I bring this up? Because it provides greater color to an already wonderfully colorful quote from one of my favorites, Charles Spurgeon, who had this to say about churches serving as Leyden jars.
It should be our ambition, in the power of the Holy Ghost, to work the entire church into a fine missionary condition, to make it like a Leyden jar charged to the full with divine electricity, so that whatever comes into contact with it shall feel its power (Lectures, p. 191).
The challenge, of course, is to understand, first, how to build a charge within a congregation, that is, how to preach and lead and serve and pray so that the church does indeed become filled with divine electricity; and then, secondly, how to to provide appropriate discharge paths so that this divine electricity might flow out of our life together and into the surrounding neighborhoods and beyond.