The priests and Levites had purified themselves ceremonially, they purified the people, the gates and the wall

Nehemiah 12:27-47

When the priests and Levites had purified themselves ceremonially, they purified the people, the gates and the wall.

I had the leaders of Judah go up on top of the wall. I also assigned two large choirs to give thanks. One was to proceed on top of the wall to the right, toward the Dung Gate. Hoshaiah and half the leaders of Judah followed them, with musical instruments prescribed by David the man of God. Ezra the teacher of the Law led the procession. At the Fountain Gate they continued directly up the steps of the City of David on the ascent to the wall and passed above the site of David’s palace to the Water Gate on the east.

The second choir proceeded in the opposite direction. I followed them on top of[g] the wall, together with half the people—past the Tower of the Ovens to the Broad Wall, over the Gate of Ephraim, the Jeshanah[h] Gate, the Fish Gate, the Tower of Hananel and the Tower of the Hundred, as far as the Sheep Gate. At the Gate of the Guard they stopped.

 The sound of rejoicing in Jerusalem could be heard far away.

At that time men were appointed to be in charge of the storerooms for the contributions, firstfruits and tithes. From the fields around the towns they were to bring into the storerooms the portions required by the Law for the priests and the Levites, for Judah was pleased with the ministering priests and Levites.

So in the days of Zerubbabel and of Nehemiah, all Israel contributed the daily portions for the musicians and the gatekeepers. They also set aside the portion for the other Levites, and the Levites set aside the portion for the descendants of Aaron.

Why?

Jerusalem is called the holy city, so the priests and Levites purified themselves ceremonially, they purified the people, the gate, and the wall.

Two choirs go in two opposite directions so they can walk before the home and remind them how difficult they had in construction, but for the blessing of the Lord, this mission was completed.

How?

Separate us from this world is our living style to every Christian, to be a holy servant before the Lord.