2 John and 3 John are the only New Testament books whose author identifies himself solely by the title "the Elder," without a name, a choice that has fed one of the more intriguing puzzles in New Testament scholarship. The early Christian writer Papias, quoted by the later church historian Eusebius, distinguished between "John the apostle" and a separate figure he called "John the Elder," both apparently active in the same region of Asia Minor around the turn of the 1st and 2nd centuries; some scholars propose that this second John, rather than the apostle traditionally credited with the Gospel and Revelation, is the actual author of 2 and 3 John and possibly 1 John as well. Others hold the title "Elder" is simply how the apostle John, by then an old man with recognized authority in his community, chose to refer to himself, without implying a separate person at all.
The letter's brevity and its late, uneven acceptance across different regions of the early church, some communities knew and used it early, others apparently did not encounter it for generations, made it one of the last New Testament books to achieve universal recognition, though once recognized its place has never again been questioned.