Although its roots can be traced back not just to the Bible, but to the ideas of Aristotle, rediscovered in the 13th Century by St Thomas Aquinas, the modern expression of Catholic Social Teaching came in an encyclical - the highest form of papal teaching - titled Rerum Novarum and issued in 1891 by Pope Leo XIII.
The Pope offered the "gift" of Catholic social thought to a troubled world.
He called on the one hand for compassion for the poor and respect for the dignity of labour and, on the other hand, for respect for property and the family - all held together by the core idea of the common good.
Catholic social teaching has the potential to do great good for society. Let's hope that it does not become the domain of the Christian Left in Britain. Liberals tend to look to government to fulfill the goals of catholic social justice, but government is only one of many players in this teaching. Individuals, families, churches, associations, and local communities have huge roles to play in caring for the poor, fostering respect for human dignity, and seeking the common good. Catholic social teaching most naturally gels with conservatism, not liberal thought.