Matthew 12:33

Either make the tree good. — Like most proverbs and parables, the words present different phases, and admit of various applications. As spoken to men of neutral, half-hearted character, they might seem a call, not without a touch of indignant rebuke, to consistency. “At least be thorough; lot principles and actions harmonise. Do not think you can produce the fruit of good works from the tree of a corrupt heart.” This, however, is not their meaning here. The men to whom our Lord spoke were not neutral, but in direct hostility to Him, and here, therefore, He presses on them logical rather than practical consistency; “make,” i.e., reckon, the tree and the fruit as having the same character. If to cast out demons be a good work, then the power from which it flows must be good also. Works of that kind do not come from a corrupt source.