The first and most pervasive problem with alleged biblical prophecies is vagueness. Many events that the Bible predicts are either so mundane that they happen constantly or have no time limit and are bound to happen if we wait long enough—sometimes both. Here are a couple of examples:
- "...scoffers will come in that last days, walking according to their own lusts, and saying, 'Where is the promise of his coming?'" (2 Peter 3:3-4)
- "And you will hear of wars and rumors of wars. ... For nation will rise against nation, and kingdom against kingdom. And there will be famines, pestilences, and earthquakes in various places." (Matthew 24:6-7)
Because he couldn't really predict the future. And when he tried, he failed.
Another example of vague "prophecy" is the alleged phenomenon of scientific foreknowledge. For example, some Christians marvel at Leviticus 17:11's pronouncement that "the life of the flesh is in the blood," saying that ancient people couldn't have known this without divine inspiration. Two problems: First, this would be easy to conclude simply by watching any animal bleed to death. Second, blood isn't even the only part of the body that's essential to life. One could just as easily say "the life of the flesh" is in the lungs, heart or brain.
Speaking of brains, the Bible never mentions them as the center of thought and consciousness—not even once. However, it does contain countless references to thoughts and feelings emanating from the heart and even the kidneys. It seems like if God wanted his book to be scientifically accurate, this might have been an important thing to get straight. Yet in fact, the Bible is chock full of such scientific errors.
Another problem with biblical prophecies is that many of them weren't even meant to be prophecies at all, and in fact mean something very different when put into their proper context. For example, Matthew says that after Jesus' birth, his family took him to hide in Egypt, thereby fulfilling a prophecy that said, "out of Egypt I called My Son." Not bad, right? Well, take a look at the original context:
"When Israel was a child, I loved him, and out of Egypt I called My son. As they called them, so they went from them; they sacrificed to the Baals, and burned incense to the carved images." (Hosea 11:1-2)Funny, I don't remember Jesus being called Israel or making sacrifices to other gods. That's because he didn't, and this passage in Hosea is about the Israelites escaping from Egypt. Apologists try to spin passages like these as "double fulfillment," happening once in the original context and once at a later date. They can call it whatever they like, but what it amounts to is selectively reading into passages that often were never meant to be prophecies in the first place. Every bit of the Old Testament is a potential case of double fulfillment. With that much source material to work with, how could Jesus not have "fulfilled" some of it purely by chance?
There are two other ways the Bible can outright cheat to make it appear as though prophecies have been fulfilled. First let's take the previous example. Matthew's account of Jesus' flight to Egypt is mentioned nowhere else in the Bible, and directly conflicts with Luke's account. Here's what probably happened. The writer of Matthew is scouring the OT for passages about Jesus and stumbles across one where God mentions Israel as his metaphorical son. Perfect! Just replace Israel with Jesus, make up a story where he must escape to Egypt, and presto! Another prophecy fulfilled.
I'll use the book of Daniel to illustrate the second method of cheating. As it turns out, Daniel makes predictions about various wars and conquests with remarkable accuracy right up until about Daniel 11:39. The book is set as though it was written by Daniel under the rule of Nebuchadnezzar II, around 600 BCE. But based on evidence in the text, biblical scholars believe the book was actually written in about 165 BCE, and that the writer tried to pass off the book as older than it really was. The so-called prophecies described events that had already taken place.
Which brings us to our final problem with biblical prophecy: Contrary to what Christians believe, some of the prophecies in the Bible flat-out failed. Everything up through Daniel 11:39 had already happened, but from Daniel 11:40 onwards the writer genuinely does try to make predictions—and of course, absolutely none of them were fulfilled. He prophesies, among other things, that Antiochus Epiphanes would utterly conquer northwest Africa, including Egypt. It never happened. By the Bible's own standard, Daniel was a false prophet and should have been put to death.
As we've seen, there are a host of problems with prophecies in the Bible. Without exception, each one suffers from some combination of vagueness, lack of time limit, lack of indication that they were even meant as prophecy, fabrication of events, forgery produced after an alleged fulfillment, or outright failure. None of these would be present if the Bible was truly the inspired word of God.