The earlier saying had warned against laying up food “treasures” that could be “eaten” by the eating-thing/worm. Jesus here uses an analogy from nature. Birds do not “treasure up” food in a barn; still, they eat. There is no implication that birds lead idle lives. The difference is not in the effort required to sustain life but rather in the “gather[ing] into barns.” The people to whom Jesus spoke in the Old World would certainly be worried about their next meal. Jesus promises them that they need not be anxious because God will give them their daily bread. He does not promise rich food or unlimited quantities of food but a sufficiency. Their crops will be sufficient. Their labor will be sufficient.
Comparison: There is no change from the Matthean text.