How do you know there is a God?


How do you know that a personal God exists? What convinces you that there is a God who loves and cares for us?


You might wish to refine your questions. That is, which do you mean us to answer first? The question of a personal God necessarily follows the question of the existence of any God.


My question concerns the existence of a personal God, because I do not believe the Creator of the Cosmos would choose not to interact with his creation.


So, I am assuming that you mean to posit the existence of an indifferent God, much like that of Deism, who constructs the cosmos and then abandons it.

The problem with this line of thinking, to my mind, is that it neglects all or some of the properties of what the creator god must be. That is, creation, being created out of nothing, in order to endure, must logically require at least the upkeep and support of this creator. Therefore some minimal level of interaction must be extant.

Further, it fails to answer the necessity of creation. A creator God must possess, in some respect, everything that exists within creation and therefore have no need of any hypothetical benefit such creation could provide. If this creator is indifferent, no motive exists. If, as Christians believe, God is a communion of love that seeks to expand participation in His reality, then the motive of creation becomes one of gratuitous gift. Moreover, such a creation would be one in which the creatures are created for and thus crave such communion. This therefore necessitates an even more intimate level of interaction.

It therefore seems that, by virtue of our continuing existence and our craving not only for the community of others but of God, as evidenced by the persistence of religion, that the evidence leans in favor of a God Who does interact with His creation and Whose desire for such intimacy may very well include His becoming one of us.


The heavens declare the glory of God; the sky proclaims its builder’s craft. One day to the next conveys that message; one night to the next imparts that knowledge. There is no word or sound; no voice is heard; Yet their report goes forth through all the earth, their message, to the ends of the world. (Psalm 19:2-5)

In other words, creation itself shouts that a Creator exists.

From a philosophical standpoint (and I am no philosopher, I leave that to people much smarter than myself), nothing exists without a cause preceding it (something had to cause everything that is; nothing came into existence by itself). If you could go back to the first “thing” that existed, and ask, “What caused it?”, you would have to admit that there must exist an “uncreated” first cause of everything that is. We call that first cause “God.”

From a more scientific standpoint (and I’m not much of a scientist either, so someone else might be able to explain it better), there is such order and complexity in the universe that it could not possibly have come about by random chance. It is a law of physics that, over time, things tend to become more random, not more structured. To say that the order existing in the universe happened randomly makes less sense than to say that you could throw millions of random letters up in the air and that they could “randomly” fall down in the exact order of the text of the Encyclopedia Britannica (or your favorite voluminous work of literature). I have not done the math, but others have. So the “first cause” mentioned in the previous paragraph must be a highly intelligent, rational being.

Some reading that might interest you:
*]I Wish I Could Believe by Juan L. Pedraz, SJ (unfortunately out-of-print, and the used copies I have seen online run about $40; the original price of the paperback was $7.95)
*]Faith and Reason: Why Christianity Makes Sense by Austin G. Schmidt, SJ and Joseph A. Perkins, A.M. (starts with the existence of God; then how that God is a personal God; then how that God is involved with creation; then why the Christian concept of God makes the most sense)
*]The Science Before Science: A Guide to Thinking in the 21st Century (written by a physicist; links scientific knowledge with philosophy and religion; excellent, but not an easy read)


Something rather curious occurred in the 20th century: modern science made the disbelief in a Creator increasingly irrational. Yes, that’s right. From several different quarters and disciplines of physics, it was revealed to us that atheism is really terribly illogical.

  • There’s the old argument from design, but with many new nuances. Basically, the physical properties of the universe have been ‘tuned’ to produce life to such a degree that it was obviously “designed”. As one example, if but one constant was different by 1 part in 10^120 (that’s 1 with 120 zeros after it), there could be no life in the universe.


  • The notion of materialism - that the only thing that exists is physical matter - has been completely debunked (though this doesn’t stop certain “intellectuals” from ignoring this). Quantum mechanics showed us that the concept of “mind” must exist and that it must be a non-physical entity. An airtight logical proof has been put forth that demonstrates that the human mind cannot be a machine - cannot be purely physical. (See Dr. Stephen Barr’s “Modern Physics and Ancient Faith” for more on these topics.)


I choose to believe because life would be meaningless and hopeless without God. God confirms my beliefs because He chooses to interact with various folks in my life. Various folks (friends or relatives) have had spiritual encounters (near death/after death experiences).

My readings about the saints and their accompanying miracles throughout history makes it just about an absolute certainty that Jesus is who He claims to be.

And various events in my own life proves to me that things don’t just happen in a totally random manner. I haven’t witnessed any first hand miracles, but I would not be too surprisd if someday one occurred.


Cultural background, & nurture, have a great deal to do with it - if I had been brought up RC, I might well have had very different ideas.

God can be talked about till Kingdom come - but talk isn’t going to prove anything. Only experience can do that. It’s like swimming - going on and on and on on and on about it, is no replacement for doing it, for experiencing it. Nor is any amount of talking about water any use whatever to man dying of thirst: only drinking the stuff is any use: the lectures can come later. Reason is far too superficial & far too limited to be really useful in revealing God - He must do that, or not. But constructing Towers of Babel by writing billions of books about Him is absurd: it’s an attempt to come to God on our terms: so it’s doomed from the start. God must come down to us - we can’t ascend to Him.

So with God - wittering on about Him is useless as a replacement for experiencing Him: having faith is something that nobody can have in place of someone else. One can say what the “mechanics” are, & even go into vast detail about them - but burbling on about faith, is not the same as having faith. Knowing about God is useless without knowing God - they are in no way the same. I think this is strongly implied in 1 Corinthians 13: “If I know all mysteries, and have not charity, I am nothing”.


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