In this article cited below, the author says "Katz tried to see a reference to all three letters by taking “catholic” to refer not to the church but to the “catholic epistle” of John, namely 1 John." Who is Katz here? I searched for Catholic NEAR John AND Katz. https://sermons.logos.com/sermons/770949-first-john-introduction-canonicity-of-johannine-epistles