I want to define the term "rational" so that there's no confusion about what I mean by that, since being rational and "making sense" is going to come up from time to time.
Sometimes there's this notion of rational meaning cold, calculating, machine-like, as in "coolly rational". That's not what I mean when I use the term. The definition provided by WordNet: "consistent with or based on or using reason; 'rational behavior'; 'a process of rational inference'; 'rational thought'", pretty much nails the way I would use the term. (And there's plenty of room for mercy, forgiveness, and self-sacrifice in a rational world.)
It should go without saying that Of course God is a rational being. But that's isn't how you'll hear Him described by the anti-theistic (in a future post I'll get into the fundamental misunderstandings of the nature of God held by anti-theists that cause them to see God as arbitrary, callous, and capricious).
Simply put, God does things for a reason, an understandable reason. Sometimes He does so explicitly: Why did God "send his only begotten Son, that whosoever believeth on him should not perish, but have everlasting life"? Answer: Because He "so loved the world". (John 3:16)
Sometimes the reason is implicit: Why does a rock fall? Because gravity acts on it. (Bonus question: How does gravity work? Answer: Still working on it... :-)
When you study the world and the universe, cause and effect is clearly the Law of the land. Every effect has a cause, and the relationship between that cause and its effect can be uncovered and understood. Sometimes the cause, or the relationship between the cause and effect, is extraordinarily complicated, but we persevere because there has not been a single known instance of an effect for which a coherent cause was not eventually found.
In human and spiritual relationships, cause and effect operates there as well, though because of the marvelous complexity of the participants in these relationships the exact cause and its relation to actions (the effects) is not always so clear. Think about everything you do--isn't there always a reason for every single act you perform? Most of these are mundane: I'm hungry, therefore I'll grab some chips; I'm having a hard time seeing, I'll turn on a light. Sometimes the act is ill-conceived, but you still had a reason that you may have to concede now is that it only seemed like a good idea at the time.
Everything we know of God as given in the Bible indicates that God does things for understandable and sensible reasons, which makes God rational. We're molded in the image of God, that makes us rational. The universe operates by cause and effect, which reflects and reinforces the idea of God's rationality.
There are two points here:
- When there's competing candidate causes for a given effect, the one that is most consistent with the cause and effect of the universe, due to its reflection of the rational nature of God, is the cause most likely to be correct.
- When causes have been identified that are going to execute within a certain context, the anticipated effects will be those most consistent with the rational nature of God and the cause-and-effect universe.
Knowing that God is rational gives us a solid foundation for learning and comprehending everything around us, and allows us to use our senses and our intellect to make judgments about what makes sense and what doesn't, which advances us further down the path to Truth.