Pro bono publico and quid pro quo mean for the public good and this for that respectively. Pro phetes means to speak for. It is from this phrase that we get the word prophet. The prophet of God is one who speaks for God.
The Hebrew prophets spoke for justice. They spoke for the poor. They spoke out against systems that left the widows and orphans unattended. They were not, as I hope most readers understand, fortune tellers. Everything they said was contingent on present action. IF you continue to disobey God’s law, THEN God will give you into captivity.
I think a good name for Christians who play a similar role in modern culture—warning the nation of the evils and dangers of neglecting the poor and the outcast—is Prophetic Christians. Just as Evangelical Christians are those who see the most important thing about the faith as spreading it to others so that these new converts may receive Salvation, Prophetic Christians would be those who see the most important thing about the faith as improving this world and bringing the Kingdom of God to earth.
Jesus taught us, we Prophetic Christians, that when we speak for the outcast, when we speak for the poor, when we speak for those without a voice, we speak for God.