Well, I’m an atheist (former Catholic), so my opinion is going to be slightly different from what is likely to be the consensus. I do not believe miracles occur, or more precisely, I do not believe “miracles” are the result of divine intercession.
Reality has what is called a “probability set”. A probability set contains all probabilities from 0 (impossible) to 1 (certain). Some events are more likely to happen than others. For instance, it’s almost an absolute certainty (i.e. close to 1) that either a Democrat or a Republican will be elected as President of the United States. Other events are less likely to happen (i.e. close to 0) - someone who catches a deadly disease may not be cured. But the fact at the end of the day, is that each event is
bound to happen: A Democrat/Republican will be elected into office, and someone will be cured from a deadly disease. The only difference is the likelihood of each event happening. So, we find that “miracles” are really just a statistical matter, not one due to divine intercession.
This explains the problem you have encountered: How do you distinguish between a “true” miracle from a coincidence? In actuality, you can’t. A miracle that occurs to someone praying is everywhere and anywhere always a coincidence. This explains why only a small number of people with deadly diseases end up being cured, which for us atheists is problematic as it indicates a biased God (on the assumption that he existed). For us atheists, the fact that only a small number of people are cured is proof of being a statistical phenomenon rather than a divine phenomenon. In addition, most miracles attributed to saints are hear-say, rumours, falsehoods and sometimes even outright lies. St. Padre Pio, for instance, has unfortunately been at the very brunt of this. He has been claimed to do all sorts of things, from bilocation (appearing in two different places at the same time) to miraculous healing. A brief Google search will reveal to you that there is no objective proof of these miracles ever occurring. Same thing for the claim that frequent prayer of the rosary saved two Jesuits from being hurt in a nuclear bomb explosion.
We place our belief and hope in the ingenuity of Mankind that scientific achievements made will be able to help the worst off in society, from the very ill to the very poor. It is a historical fact that Man has raised his potential life expectancy not by prayer, but only because of scientific advancements. We look to certainties rather than miracles. And science is helping what was once perceived to be a miracle, a certainty.
Many theists have tried to cover up their tracks so to speak with regards to the problem of miracles. St. Therese of Lisieux, as an example, had a methodology called the “Little Way”. She was a rather humble character, but one of the flaws of her methodology was attempting to see God in everything. This mainly encompassed the “little things”. We as atheists find such view of the world problematic, because the “little things” are essentially what is inevitably going to occur anyway. Whatever happened to the God who helped part the Red Sea for Moses, or made the sun stand still for Joshua? Seems like he has gone reticent all of a sudden. The fact that miracles rarely occur is itself a proof of God’s non-existence, or at least a revamping of how traditional theology perceives God. Epicurus, an Ancient Greek philosopher, summed it up best when he postulated:
“
Is God willing to prevent evil, but not able?
Then he is not omnipotent [all-powerful].
Is he able, but not willing?
Then he is malevolent [evil].
Is he both able and willing?
Then whence cometh evil?
Is he neither able nor willing?
Then why call him God?”
That’s just an outline of why atheists do not believe in miracles. You may be interested in several philosophers, such as David Hume and Bertrand Russell. They have all spoken/alluded to the problem of miracles at one point in their career. Of course, this isn’t to dismiss what miracles you or anyone else on these forums may claim to have experienced. I understand that it’s an emotional subject for many, but this is what reality eventually boils down to, as I - a previous practicing Catholic - found out the “hard way”.
I wish you the best in your future endeavours

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