Ambrose of Milan
Catena Aurea · Lukasevangelium 1
And there appeared unto him an angel of the the Lord standing on the right side of the altar of incense. And when Zacharias saw him, he was troubled, and fear fell upon him. But the angel said unto him, Fear not, Zacharias: for thy prayer is heard; and thy wife Elisabeth shall bear thee a son, and thou shalt call his name John. And thou shalt have joy and gladness; and many shall rejoice at his birth.
Or, as follows; Divine mercy is ever full and overflowing, not narrowed to a single gift, but pouring in an abundant store of blessings; as in this case, where first the fruit of his prayer is promised; and next, that his barren wife shall bear a child, whose name is announced as follows; And thou shalt call his name John.