How did the early church fathers interpret the "rock" of Matthew 16?
I would say if this were the lightning round we could say, true.
The notion that Peter himself was the rock rather than his confession being the rock seems first to be articulated by a bishop of Rome in the third century.
Now, the third century is very early relative to us, but it's a long time after Jesus—two hundred and fifty years after Jesus. And this is a sort of solitary point of view of the Bishop of Rome initially, not even followed up by all later bishops of Rome in the ancient church period.
So yes, I think, generally speaking, the notion that Peter himself was the rock is a relatively late development in the Western church—never in the Eastern church—and in a later part of the ancient period. And many earlier interpreters would've seen that differently.
This transcript is from a live Ask Ligonier event with W. Robert Godfrey and has been lightly edited for readability. To ask Ligonier a biblical or theological question, just visit Ask.Ligonier.org or message us on Facebook or Twitter.