Read this passage from "Recessional." What is the speaker contrasting in these lines?

The tumult and the shouting dies;

The Captains and the Kings depart:

Still stands Thine ancient sacrifice,

An humble and a contrite heart.

Lord God of Hosts, be with us yet,

Lest we forget-lest we forget!

The recent ceremony and the ancient sacrifice

The Captains and the Kings who are departing

The tumult of the crowd and the shouting of the people

The humble hearts and the contrite hearts

The speaker in the given lines is contrasting the tumult of the crowd and the shouting of the people.

Explanation:

Even without the waging of the battle and the shouting of the people has already died, there is no single cause or the reason for forgetting god. The sacrifices which have been made are still relevant in todays world. One should change their attitude towards god because of any reason. Because no such reason is powerful to change one's attitude towards God.