The saying about the birds picked up on the treasures of food. This saying elaborates upon the treasures of clothing. Just as we should not be anxiously concerned for excess food, we should not be anxiously concerned for excess or sumptuous clothing. Note that the reference is to a beautiful, but natural, flower. The beauty of the flower is sufficient. It is clothed already, and in no need of excess. Just was we have no need for excess height, we should have no need for excess or sumptuous clothing. Note that the lilies do not toil nor spin. These two words are meant to evoke the similar parallels to food and clothing. The toil refers to the labor in the fields to produce food, and the spinning of course evokes clothing.
Textual: There is no change from the Matthean text. The Lukan parallel is Luke 12:27. The Greek text for that verse has the more natural pairing of spinning and weaving. The dual reference to clothing is more appropriate to the context of the lilies than the Matthean toil and spin.