The Pharisees understood life and faith as literal adherence to the Law; by this criterion they judged others, judged themselves, and judge Jesus. If they could show that He was breaking or ignoring the Law, they could declare Him a blasphemer, unrighteous, someone who was a danger to the people of Israel. Buth they struggled to find unorthodoxy in His teachings, and so conspired with their disciples and others to trap Him by posing what they regarded as trick questions, impossible to answer without getting into one kind of trouble or another. Jesus’ reply showed once again how radically different was His approach to the Law of God. He simplified the question using what we would term lateral thinking: shifting the whole basis of the argument. He applied the supreme principle of giving to God what belongs to God, with the consequence that anything else is a relatively insignificant detail.
How do we strike a healthy balance between law and freedom? How do we avoid being like the Pharisees, living the letter of the law, but ignorant of its spirit? What matters above all else is love and service of God and of neighbor: everything else can then be seen in its proper place.