Oecumenius

And he says that one hundred and forty thousand were sealed; for many were those who believed in Christ from among the Jews, who owed their salvation from the common destruction to this number. And those who spoke with Paul in Jerusalem bear witness: "Look, brother, how many myriads of Jews have believed." (Acts 21:20) It was not only reasonable to spare the faithful but also those who, in ignorance and deception, cooperated with the crucifixion of the Lord, concerning whom He said: "Father, forgive them; for they do not know what …

Commentary on Revelation ↗

Methodius of Olympus

I am one in the choir with Christ dispensing His rewards in heaven, around the unbeginning and never-ending King. I have become the torch-bearer of the unapproachable lights, and I join with their company in the new song of the archangels, showing forth the new grace of the Church; for the Word says that the company of virgins always follow the Lord, and have fellowship with Him wherever He is. And this is what John signifies in the commemoration of the hundred and forty-four thousand.

Methodius Discourse VI. Agathe ↗

Bede

And I heard the number of those who were sealed, etc. This finite number signifies the innumerable multitude of the whole Church, which is generated from the patriarchs, either by descent of flesh or by imitation of faith. For if you are Christ's, then you are Abraham's seed (Gal. 3). For the increase of perfection, it pertains that twelve is multiplied twelve times, and to the total is perfected as a thousand, which is a solid squared number, signifying the stable life of the Church. …

Commentary on Revelation ↗

Alcuin of York

And I heard the number of them that were signed, an hundred forty-four thousand were signed, of every tribe of the children of Israel. It is a definite number put for an indefinite one, and it does not refer only to the twelve tribes of Israel, but all the Church, in the elect, is represented by it. …

Commentary On Revelation ↗