Matthew 18:1

ἐν ἐκείνῃ τῇ ὥρᾳ. The preceding incident and our Lord’s words had again excited hopes of a glorious kingdom on earth. We may suppose that Jesus and St Peter were alone when the last incident happened, they had entered the house (probably Peter’s) and were now joined by the other apostles who had been disputing on the way (ἐν τῇ ὁδῷ, Mark).

ὁ μείζων (τῶν ἄλλων) as distinct from the superlative, the comparative contrasts an object with but one standard of comparison, μέγιστος would have implied three or four degrees of rank among the Twelve. Winer, 303 and 305.