Ambrose of Milan

Or, He asked the blind man to the end that we might believe, that without confession no man can be saved.

Catena Aurea by Aquinas ↗

Gregory the Dialogist

And it should be noted what He says to the blind man as he approaches: "What do you want Me to do for you?" Did He who was able to restore light not know what the blind man wanted? But He wishes to be asked for that which He foreknows both that we will ask and that He will grant. For He urges us persistently to prayer, and yet says: "For your heavenly Father knows what you need before you ask Him." Therefore He requires to be asked for this reason: He requires it in order to arouse the heart to prayer. …

Forty Gospel Homilies, Homily 2 ↗

Bede

And when he approached, he questioned him saying: What do you want me to do for you? And he said, Lord, that I may see. Did He who could give light not know what the blind man wanted? But He wishes that this be asked, which He knows beforehand that we would ask and He would grant. For He urgently admonishes us to prayer, and yet He says: Your Father knows what you need before you ask Him (Matthew VI). Therefore, He requires this, that it be asked; He requires this, that the heart be stirred to prayer. …

On the Gospel of Luke ↗