The First Cause
All entities that can exist can be divided into two kinds. There are entities which do not necessarily need to be as they are; they could be different, or they might not exist at all. Entities like this are called 'contingent entities'. This website is contingent. It could be worded differently; it is possible that it would never have been written at all. Because contingent entities could be different (or non-existent) there needs to be some other entity -or entities - to explain why they exist. These notes are explained by the author who decided what they would contain and how they would be worded.
The other kind of entity is described by the word “necessary”. A necessary entity must logically exist as it is; such an entity could not be different and must exist. A necessary entity needs no cause or explanation.
The important point here is that every contingent entity needs at least one other entity to explain its existence. The existence of a contingent entity means that there must be some other entity. If this entity is also contingent, then another cause or causes is required, and a chain (or network) of cause and effect is perceived. However, such a chain would itself be contingent, and requires a cause. In the end the whole system requires a necessary entity to cause its existence.
The whole universe is, of course, contingent. It came into existence and therefore requires a creator. However many stages one supposes there were to bring the universe into existence, there must be a necessary entity behind everything.
This necessary entity is God.
The existence of God is needed to explain why there is something rather than nothing. Without God there is no reason for anything to exist. God is the necessary entity who underlies the whole of existence.
This tells us several things about God.
The first of these is that God is not part of the creation; he is outside the universe and independent of it. This picture of God is entirely consistent with the teaching of the Bible, but is completely different from the teachings of polytheistic religions like those of ancient Greece and Rome, the many gods of the Canaanites, or for that matter the gods of Hinduism.
The polytheist gods are supposed to have parents, which means that they came into existence; they are not eternal and therefore need a cause. The polytheist gods were often part of the working of the universe; they were supposed to cause rain and thunder, or to make crops grow.
God is outside the universe. He made nature, and this includes the laws of nature and hence the mechanisms which cause rain, the growth of crops and even keep life itself in existence.
The second is that God has no limits other than those he chooses to place on himself. The reason for this is that as God is necessary, then no other entity is needed to explain why he is as he is or acts as he acts.
God, then, is the entity who is responsible for the existence of the universe, and indeed for the whole of reality. The name by which God chooses to be known is significant:
"Then Moses said to God, 'If I come to the people of Israel and say to them, "The God of your fathers has sent me to you," and they ask me, "What is his name?" what shall I say to them?' God said to Moses, 'I AM WHO I AM.' And he said, 'Say this to the people of Israel, 'I AM has sent me to you.’” (Exodus 3:13,14)
The God who exists without cause and who is responsible for the existence of everything else identifies himself by the name “I Am”. This statement was written more than a thousand years before the birth of Jesus. It is unlikely that the writer was aware of the concepts which give rise to deductions from first cause; in spite of this the name of God is a clear reminder of these deductions.