It would probably strike most of us as strange, to ask the question: which is more important: in or out? We would not know how to answer the question, since it makes no sense to us. Our first reaction might be to say: it’s impossible to think of “in”, without, at the same time, thinking of “out”. They go together, like the hand in a glove. They cannot exist apart from one another.
But, then, on second thought, we might have to admit that, well, yes, it probably is possible to think of an “in”, without simultaneously thinking of an “out”. There is probably an instance of an “in” to which there corresponds no “out”, such as placing a coffin in the ground, without eventually having to think of the coffin coming out of the ground, or of an idea coming into my mind without it eventually coming out of there in some form or fashion. Or, on the other hand, there may be an example of an “out” which is not followed by an “in”, such as going out of a classroom, on the last day of one’s educational program, never to go back into this classroom again, or going out of particular house that has served as a home for me, never to enter it again, as I move to another location.
But, apart from these rather bazaar examples, “in” and “out” form a pair that go together. The best example of “in” and “out” is the waves of the sea. The turf rolls onto the seashore bordering it, only eventually, sooner or later, to roll out. It’s impossible to think of waves cascading across the shoreline fronting them, without their rolling off the beach again and back out into the body of water from which they initially came. Otherwise they would continue to roll in and roll in and eventually submerge the land mass over which they flow, leaving behind them a huge void, now emptied of any wave of water, relocated now in another place. But this would spell the end of the “in” and “out” waters of the waves.
Such a motion has a rhythm all its own. It can almost be timed in a predictable way, with its “coming in” requiring several minutes, and its “going out” lasting a comparable period of time. A kind of mutual dependence develops between the incoming and the outgoing wave, much like the going up and the coming down of a ball thrown into the air. Whatever goes up must come down, sooner or later, even the satellites that we launch into outer space, so long as the law of gravity prevails, which establishes that what goes up will come down, unless something escapes its force.
And so our scientists, keen to fasten on the energy resources available, have latched onto the rhythm of the seas, with their waves rolling onto the shores of the lands bordering them, then receding back into their watery origin, there to be re-energized so as to again spill over the land mass containing them. The rhythm of in and out has a power all its own, which can be harnessed into an energy resource that activates our machinery empowering our productivity, just as coal, gas, or electricity does. There is an interdependence between the “out” and the “in”. If the “in” tuckers out and loses all its force, then the “out” fails to materialize and their interaction comes to an end.
God makes use of this “in”-“out” interplay. After all, He is the acknowledged source of their interaction. So our scriptures speak of Him coming “into” our midst for a period of time, with the birth of the Lord Jesus, then “going out”, reverting to the place from where He came. His entrance among us empowered us as He charged our batteries (the sacraments) and established a power plant (the church) among us, before “going out” once again, leaving us behind but not without an energy resource, thanks to which we are empowered to move onto the shore of our world, like the waves of the sea, only to eventually flow back into the source from which we came (the church), to be re-energized.