Theodoret of Cyrus
Consider Ezekiel 15:1 Will the sustenance be required for the task? And indeed, it will not be complete for labor; how much less will it serve any purpose if the fire consumes it entirely? If it is unfit for any work before being exposed to the flames, it is even less valuable after it has fallen victim to fire. After elaborating on these points, he also provides the explanation of the parable.