John 10:29 is a place where text-critical and literary-theological decisions intersect in a complex way. Literary-theological reasoning has driven many interpreters not to choose the ὃ … μεῖζον reading, while the NA editors have preferred this reading for text-critical reasons. The purpose of this study is not to offer a definitive answer to the text-critical question itself. Rather, I aim to explore the neglected possibilities of how one could make sense of the ὃ … μεῖζον reading—an option unbeloved by several interpreters for literary-theological reasons—in light of literary and theological characteristics of the Fourth Gospel. The central question of the article is, What noun does the enigmatic neuter singular relative pronoun ὅ (“that which”) refer to? The examination of five candidates for the referent demonstrates that the Father’s name makes the best sense of the phrase.