"At last the wall was completed to half it's height around the entire city, for the people had worked with enthusiasm" Nehemiah 4:6

The story in Nehemiah chapter 2-4 took place after the Israelites had returned to Judah but were not making progress because they couldn't pray to God; they had no temple were they could make sacrifices unto God because the temple had be destroyed and the walls of Jerusalem had fallen. They couldn't build back the wall.

They were sad, lived in anguish though in their own towns. The only way out for them is to seek God's face, but how when they don't have a temple were they will pray and make sacrifices unto God. So they needed to urgently rebuild the temple and even the walls of the city to save them from enemies.

Then Nehemiah who was living in another place though also an Israelite but serving a king of another nation. He was a man after God's heart, he prayed. "O LORD, God of heaven, the great and awesome God who keeps His covenant of unfailing love with those who love Him and obey His commands, listen to my prayer! Look down and see me praying night and day for Your people Israel. I confess that we have sinned against you" Nehemiah 1:5-6. "Please grant me success today by making the king favorable to me. Put it into his heart to be kind to me" (1:11B)
http://www.ackcity.net/prayerandenthusiasm.htm