Regular readers of this blog will know I was recently at the Micah Global Conference in Lima, Peru. The theme that ran through the meetings was shalom. The word goes beyond "peace" to include salvation and well-being. One important point to make is that without justice there can be no peace.
Micah Global takes its name, of course, from Micah 6:8
He has shown you, O mortal, what is good.
And what does the Lord require of you?
To act justly and to love mercy
and to walk humbly with your God.
Acting justly or doing justice is a fundamental Christian responsibility. As a disciple of Jesus Christ we cannot avoid the idea of doing justice. Doing justice has many aspects to it such as advocating for those who cannot speak for themselves (Proverbs 31:5), protesting injustice etc. I would suggest that living the Lordship of Jesus Christ sums up well what doing justice is.
The earliest Christian statement of faith was simply "Jesus is Lord" begs the question Lord of what? This put the first Christians on a collision course with the Roman Empire. Romans said that "Caesar is Lord". The Christians were saying, "No, Jesus is". This is why the Christians were persecuted.
Jesus taught us to pray "may your kingdom come, may your will be done on earth as it is in heaven." This very much sums up the ideas of justice. Justice is not being fair it is siding with the victims as Jesus did, ultimately upon the cross.