Deuteronomy 1:9-18 recounts Moses appointing judges. He calls for wise, understanding, and experienced leaders who would judge with righteousness and without any partiality knowing that their justice represented God's. In this way the nation of Israel would display God's character to the world.
The church is not under the covenant of Moses, but we learn about God's character in this passage. God is a god of justice and so those who love him must love justice! This applies within the church first. As the people who are a preview of God's kingdom, the church must be a place free from the divisions and prejudices present in society. Honestly examine yourself and repent if you are guilty of partiality!
Secondly, individual Christians should celebrate and promote justice because we love the Lord who is just - not because we think any society will be perfected apart from the Lord's return. An excellent place to put this into practice is the National Association of Evangelicals' Take Action page. On this page you can sign letters urging our civil leaders to act justly. See the page HERE.
Finally, Moses reminded the people that he was a mere man and could not carry the nation. Every leader apart from Jesus is the same! Jesus is our hope. Only he deserves our unwavering loyalty. He is faithful and can be trusted to preserve his people until the end. Until then, we live with courage knowing that HE is the one who upholds his people.