If you spend enough time on the Catholic internet, you might start to hear the name “Source Q” or just “Q” floating around. What is this mysterious letter? What is its relation to the gospels? Is it even real at all? Jimmy Akin answers these questions on Catholic Answers Live.
Caller: What’s your bottom line on what Source Q is?
Jimmy Akin: Q is—for folks who may not be aware—Q is a hypothetical source that has been proposed to explain certain verses that are in both Matthew and Luke. There are about 235 verses that are paralleled in Matthew and Luke, and there are enough of them that some people have proposed: “Okay, maybe Matthew and Luke are drawing on a common source.” And since the German word for “source” is “quela,” that has become called the Q Source.
Now the Q Source is possible. Some people are kind of threatened by the idea, like this is somehow a challenge to the authority of the gospels, but it’s really not. We know the Gospel authors had sources, and this is just one possible proposed source.
Some scholars treat Q as if it’s a given that it exists; I don’t buy that either. I don’t think it’s a given, I think there are other ways you can explain those 235 verses, like: maybe Matthew wrote first and Luke used Matthew as one of his sources, and he took those 235 verses from Matthew, in which case you don’t need a separate source. Or reverse it, which is what I think is the most likely view: that Luke wrote first, and then Matthew took the 235 verses from Luke, so you don’t need Q as a source once again.
But whether there was a Q source, or whether Luke copied from Matthew or Matthew copied from Luke, there are multiple ways to explain how these verses ended up—and there are other ways too—but there are multiple ways to explain how these verses ended up in Matthew and Luke, and we don’t need to be dogmatic about one particular view.
So I think Q is an interesting idea, but personally I’m skeptical of it; I tend to favor the idea that Matthew used Luke.