Cyril of Alexandria

For it is very improbable that those who despise the saving Word, and the Master of the household, will show themselves kind to His servants, and seek further blessings.

Catena Aurea by Aquinas ↗

Bede

And whoever will not receive you, as you go out from that city, even shake off the dust of your feet as a testimony against them. The dust is shaken off their feet in testimony of their labor, in that they have entered the city, and the apostolic preaching has reached them. Or the dust is shaken off so that they may accept nothing from them, not even what is necessary for sustenance, who have spurned the Gospel. …

On the Gospel of Luke ↗

Bonaventure

And since it belongs to true humility to refuse the company of no one, nor even to be burdensome to another, therefore for the perfection of humility it is added: And whoever do not receive you, that is, despising your doctrine, like those who also did not receive the Lord: John 1: "He came unto his own, and his own received him not." - And because this is a great offense, which is not to be shared in, therefore he adds: Going out from that city, that is, turning away from their wickedness, according to that saying of Numbers 16: …

Commentary on Luke, Chapter 9 ↗

Hippolytus of Rome

The beloved generates love, and the light immaterial the light inaccessible. "This is my beloved Son," He who, being manifested on earth and yet unseparated from the Father's bosom, was manifested, and yet did not appear. For the appearing is a different thing, since in appearance the baptizer here is superior to the baptized. For this reason did the Father send down the Holy Spirit from heaven upon Him who was baptized. …

Hippolytus Dogmatical and Historical Fragments ↗