Ambrose of Milan — as excerpted in the Catena Aurea on Luke 12:24-26

“: But it is a great thing to follow up this example in faith. For to the birds of the air who have no labour of tilling, no produce from the fruitfulness of crops, Divine Providence grants an unfailing sustenance. It is true then that the cause of our poverty seems to be covetousness. For they have for this reason a toilless and abundant use of food, because they think not of claiming to themselves by any special right fruits given for common food. We have lost what things were common by claiming them as our own. For neither is any thing a man’s own, where nothing is perpetual, nor is supply certain when the end is uncertain.”