When Paul calls love the fulfilling of the law, he is not saying that the ten commandments have become inoperative. In fact, he immediately proceeds to provide a summary of the second table of the law. Each of the commands he mentions entails forswearing doing evil to the neighbour. When you commit adultery, theft, and murder, you do evil to your neighbour. When you love your neighbour, you will automatically want to abstain from doing what the law forbids. For this reason, love is the key to the law and the fulfilling of its commandments in each area of life.1
8 Owe no one anything, except to love each other, for the one who loves another has fulfilled the law.