Cyril of Alexandria

The sacred Evangelist says that Mary was betrothed to Joseph, to show that the conception had taken place upon her betrothal solely, and that the birth of the Emanuel was miraculous, and not in accordance with the laws of nature. For the holy Virgin did not bear from the immission of man's seed. And what was the reason of this? …

Commentary on the Gospel of Luke, Sermon I ↗

Theophylact of Ohrid

Christ is also enrolled together with everyone. It was fitting for the Lord to be enrolled with the whole world, in order to sanctify those being enrolled and to abolish slavery; for just as, by undergoing circumcision, He abolished circumcision, so, by being enrolled as a slave, He abolished the slavery of our nature. For those who serve the Lord are no longer slaves of men, as the apostle says: "do not become slaves of men" (1 Cor. …

Commentary on Luke ↗

Bonaventure

It is shown lastly as fitting to the imperial edict, when it is added: That he might be enrolled with Mary his espoused wife, being great with child. For this had proceeded from the imperial edict. And although the Virgin had already conceived the King of heaven and earth, nevertheless she willed to obey the imperial edict even while pregnant, so that she might say with her Son that word of Matthew 3: "So it becomes us to fulfill all justice"; and through this give us an example of obeying every superior power, according to that word …

Commentary on Luke, Chapter 2 ↗