Are the Jewish God (Yahweh) and the Christian God One and the Same?
How we answer this question depends on how we view God as existing. I think most believers view God as existing in more or less the same way as, say, the coffee mug resting on my countertop or the fir tree growing in my yard; that is, as a real, individual object. This is not to say that God shares features such as color or shape with the mug or tree, but that, like these objects, it is a subsisting, fully real entity—something that might be called a substance in the western philosophical tradition.
Under this view of God, I think the answer is clear. The Jewish God and the Christian God cannot possibly be one and the same. The Jewish God consists of one person, while the Christian God consists of three (Father, Son, and Holy Spirit). This is not a mere accidental difference, as Aristotle might call it, but an essential difference. The difference goes to the very being of these entities. Two beings that differ in essence cannot be identical. To say that they could be would be like saying that being a cat could be identical to being a dog.
When I put this question about God to a well-known Christian philosopher over lunch a couple of years ago, he looked at me as if I needed my head examined. Of course they are the same, he replied. For whatever reason I didn’t ask him to explain his answer, but I suspect the justification for it went along these lines. There is one religious God that exists in an absolute and overriding sense, but the Christian tradition and the Jewish tradition simply understand this being differently. Thus, while the Christian tradition understands God as consisting of three persons, and the Jewish tradition understands it as consisting of one, there is one absolute being that exists independently of these attempts to understand it.
If this be the justification for my lunch table companion’s answer, I would argue that it commits at least one serious case of begging the question. The first question it begs is, How can we ever know that this independent God actually exists? If the answer is that the Bible tells us so, then I would observe that the only God the Bible talks about is the one in the New Testament, which is the Christian God, and the one in the Old Testament, which is the Jewish God. The Bible tells us nothing about any higher level God that lies behind these two Gods. And even if it did, there is the question as to how we know that what the Bible says about God is true. As I observed in Religion, Power, and Illusion, there are serious problems surrounding the alleged truth of Biblical claims.
Another possible approach to the behind-the-scenes god question is that many philosophers throughout history have given us arguments to the effect that a transcendent god exists. But the problem here, as I have pointed out at length in R P I, is that the god of the philosophers is not the same god as the one espoused in Christianity and Judaism. The god of the philosophers is changeless, all knowing, all good, all powerful, and independent of the natural world, while the God of the Bible is none of these things. Furthermore, none of the arguments put forth by the philosophers is universally accepted as valid. All of them depend on assumptions that not everyone will grant.
A better approach to this question about the Christian and Jewish gods is to say that these gods exist only as elements of belief. That is to say, the Christian god exists only because certain people called Christians believe it exists, the Jewish god exists only because certain people called Jews believe that it does, and apart from these beliefs neither god exists at all. If all of these believers should suddenly die, their god would go with them and nothing would remain behind.
Belief in God is very different from the belief, for example, that three plus two equals five. The latter is relatively clear and distinct and is fairly uniform from one person to the next, while belief in God is loaded with nuances and differs greatly from person to person. Belief in God includes early recollections about what parents and teachers might have said about God. It includes hopes for what God might do for us in the future. It includes past prayers that may or not have been answered, and it includes present prayers that await answers. It includes beliefs about God’s supposed intervention in our lives (whether prayed for or not), and it is colored by church rituals and religious festivals. None of these are the same for any two people.
With this understanding, it should be clear that the god of Judaism is not one and the same with the god of Christianity. No two person’s beliefs about anything, even day-to day events, are one and the same, much less their beliefs about something so elusive and intangible as God. One person’s God is not identical to another person’s God. Even a single person’s beliefs about God on Monday cannot be said to be strictly identical to that person’s beliefs about God on Tuesday. So the conclusion is that there are billions of beliefs about God, some of them Christian, some of them Jewish, and not one of them is strictly identical with any of the others. It follows that there are billions of gods, some Christian, some Jewish, and each different from all of the others.
This last observation points up the narrowness of our question about the two gods. What about Allah, the god of Islam, and any of the hundreds (or thousands) of Hindu gods? Is the Christian god one and the same with Brahma or Vishnu of the Hindu religion? And what about Izanagi and Izanami, the primal god and goddess of Shintoism? Is the Jewish god one and the same with either of these? Our ethnocentric perspective impedes us from asking these latter questions. The answer is that no, none of these gods is one and the same with any of the others. And this fact reinforces the observation that all religious gods exist only as objects of belief. None of them exist as independent realities.
Returning to our original question about the Jewish God and the Christian God, there may be some people who think these two gods are identical, but this is just one of those idiosyncratic beliefs about god that is determined by unique religious experiences. When it comes to belief in God, practically anything is allowed. Such beliefs are not constrained by logic, science, common sense, or anything else. Someone might think that the Christian god is identical to a fire-breathing dragon on Fridays and to a green unicorn the rest of the week. Another might believe that the Christian god is identical to the god of Judaism. But there appears to be no way of validating or confirming any of these beliefs as objectively true.