In our monthly theological discussion group, a group of men and I recently discussed the Trinity. We now understand the Trinity to be: The unity of God subsisting in three distinct persons. We reviewed the different views of the Trinity, how the concept is defined in the Bible, and how it has come to be accepted as the orthodox view currently. At the close of our discussion, we began to discuss the different analogies of the Trinity. Here are a few that we discussed through the direction of Millard Erickson's book "Christian Theology."
First, we talked about the egg. The egg has the yoke, the surrounding liquid, and the shell. All of these make up the egg. The egg is like the Trinity in that it has three parts unified into one egg. This is obviously an incomplete analogy since each of the parts of the egg are not really completely separated and yet totally unified. Each part of the egg has a different nature. So the egg analogy fails.
What about the human/humanity analogy? Each of us is a human and each of us is part of humanity. While this one is simple and easy to understand, it does not stand up to the unified Trinity requirement. While each of us are unified as humans, we can be in conflict with each other as humans and thus we are not always, if even ever, in perfect unity.
Finally, one of the best examples that I have heard of is the water analogy. The Trinity is much like water in that water can be liquid, gas, and solid and still be water. This does show a three part/unified analogy of the Trinity but the problem here is that water cannot exist in these three states simultaneously....Or can it?
Mark, a Chemist who attends our discussion group informed me about a concept called 'Triple Point.' The triple point is the intersection on a phase diagram where three phases coexist in equilibrium. Or in layman's terms, it is a particular environment where water can exist as a liquid, solid, and gas at the same time. See http://www.sv.vt.edu/classes/MSE2094_NoteBook/96ClassProj/examples/triplpt.html
for a more thorough explanation. Basically, when the right temperature and pressure is applied to water, it will exist in these three states in equilibrium. So think about this analogy...
Water which is placed in an environment with strictly controlled pressure and temperature measurements can exist as a solid, liquid, and gas. It is like the Trinity in that there is a solid, a liquid, and a gas (Father, Son, Holy Spirit) existing in perfect unity (Godhead) as the same substance in three different modes. Liquid, gas, and solid are three states of water which are entirely water but also entirely different states. So the Trinity which is the unity of God subsisting in three distinct persons is like water which is the unity of water subsisting in three distinct states: liquid, gas, and solid simultaneously and in perfect unity.
If my research is correct and my logic is consistent then this may be a wonderful analogy for the Trinity...What do you think?