Theophylact of Ohrid

Cleopas makes a reproach to the Lord, who appears in the form of a fellow traveler, and says: "Are you the only one of those who have come," that is, are you the only one of the inhabitants of Jerusalem who does not know what has happened? Others, however, understood the words "of those who have come" ("are you a stranger") in this way: are you the only stranger who lives outside Jerusalem, and are so indifferent to what is happening in it that you do not know about this?

Commentary on Luke ↗

Ancient Greek Expositor

They were in truth discoursing among themselves, no longer expecting to see Christ alive, but sorrowing as concerning their Saviour slain. Hence it follows, And one of them whose name was Cleophas, answering him said, Art thou only a stranger?

Catena Aurea by Aquinas ↗

Bede

And one of them, named Cleophas, answering, said to him: Are you alone a stranger in Jerusalem, and do not know the things which have happened there in these days? They thought him to be a stranger, whose face they did not recognize. But truly, he was a stranger to them, from whose perception the glory of the resurrection already obtained was far removed from their frail nature. He was a stranger to them, from whose still uninformed faith, as yet ignorant of his resurrection, he remained a foreigner.

On the Gospel of Luke ↗

Bonaventure

And because it is not for just anyone to thrust himself into secret conversations, according to that instruction: "Do not approach a council before you are called"; it is shown from the response that this kind of discourse is public and common. And therefore he adds: And one of them, whose name was Cleophas, answering, said to him: Are you alone a stranger in Jerusalem, and have you not known the things that have been done there in these days? …

Commentary on Luke, Chapter 24 ↗