When Sanballat heard that the building work was proceeding he mocked the Jews, that is to say, mocked to demoralise and to signal to his paid minions in the city his own opposition to what they were doing. This is about the enemies of the people of God.
This is intensely interesting because it reflects what happens in every age. Our enemies in society around us – society promoting an alternative morality, society promoting atheism, unbelief – really follow very similar lines. They are confident in their position. They despise God; they despise faith in God; they despise the Christian faith in particular. They are intensely angered by us, and they mock. They assume that we are pathetic and drawing near to extinction, and we can be trampled out, we can be got rid of. This is put their motivation, their attitude. Of course it was a great mistake on the part of the Samaritans to think that the Jews were so feeble. They were feeble in themselves, but God had summoned them to build, and God was with them. But of course their enemies took no account of the divine power which was with the people of Judah. Their attitude is one of scorn and contempt, so they underestimated the Judeans and what they could accomplish under God. The world would underestimate us too. It doesn’t underestimate us in ourselves – in ourselves we have no power – but underestimates what we are when we have our God with us, hearing and answering our prayers, and empowering our efforts.