George Leo Haydock, on Luke 1:18

“And Zachary said to the angel: Whereby shall I know this? for I am an old man, and my wife is advanced in years.”

“Whereby shall I know this? Zacharias could not question the Divine Power, but he doubted of what the angel told him. (Witham) — It was customary with the Jews, when they heard that any wonderful event was to take place, to inquire whether the Almighty had manifested his will by any supernatural sign. Zacharias puts this question to the angel, not through any doubt concerning the omnipotence of God, but because what was promised could not be compassed in the natural order of things: for, I am an old man and my wife is advanced in years. (Dionysius)”

Imported from an open dataset — not yet checked against the printed edition.