Latter half of *second* century. JH, in case you didn't know, second century refers to the 100s (not 300s). And Kelly qualifies this by saying "at the latest" -- meaning, it could have happened earlier. Whether it did or not is inconsequential - the point is that the term was used at a very early point, is not treated by Ignatius as a recent invention, and was used in response to many other heretical sects running around claiming to be Christian.
Regardless, you still have close to 200 years after the apostles died, even if I accept this man's figures, before the catholic church was formed enough to have taken the name.
Nearly 200 years is almost 5 1/2 generations of people, what was going on all that time before your church started coming on the scene? (^g^)
what was going on all that time before your church started coming on the scene?
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Same thing it's been doing since Christ founded it in 33AD - dispensing God's graces through the Sacraments and teaching people how they can be saved by Christ.