Pseudo-Chrysostom — as excerpted in the Catena Aurea on Mark 1:4-8

“(Vict. Ant. e Cat. in Marc.) But lest he should be thought to say this by way of comparing himself to Christ, he subjoins, Of whom I am not worthy, &c. It is not however the same thing to loose the shoe-latchet, which Mark here says, and to carry his shoes, which Matthew says. And indeed the Evangelists following the order of the narrative, and not able to err in any thing, say that John spoke each of these sayings in a different sense. But commentators on this passage have expounded each in a different way. For he means by the latchet, the tie of the shoe. (non occ.). He says this therefore to extol the excellence of the power of Christ, and the greatness of His divinity; as if he said, Not even in the station of his servant am I worthy to be reckoned. For it is a great thing to contemplate, as it were stooping down, those things which belong to the body of Christ, and to see from below the image of things above, and to untie each of those mysteries, about the Incarnation of Christ, which cannot be unravelled.”