'The Bible tells us to love our neighbors, and also to love our enemies; probably because they are generally the same people.'
Those words from Gilbert Keith Chesterton were certainly true in Nehemiah's situation. His arrival in Jerusalem was a threat to Sanballat and his associates (Neh. 2:10), who wanted to keep the Jews weak and dependent. A strong Jerusalem would endanger the balance of power in the region, and would also rob Sanballat and his friends of influence and wealth.
When things are going well, get ready for trouble, because the enemy doesn't want to see the work of the Lord make progress. As long as the people in Jerusalem were content with their sad lot, the enemy left them alone; but, when the Jews began to serve the Lord and bring glory to God's name, the enemy became active.
Opposition is not only evidence that God is blessing, but it is also an opportunity for us to grow. The difficulties that came to the work brought out the best in Nehemiah and his people. Satan wanted to use these problems as weapons to destroy the work, but God used them as tools to build His people. 'God had one Son without sin,' said Charles Spurgeon, 'but He never had a son without trial.'
If we spend time pondering the enemy's attacks, we will give Satan a foothold from which he can launch another attack even closer to home. The best thing to do is to pray and commit the whole thing to the Lord; and then get back to your work! Anything that keep you from doing what God has called you to do will only help the enemy.
God says: "Be on your guard; stand firm in the faith; be men of courage; be strong" (1 Cor. 16:13, niv)