Historically, Europe has been shaped by the Christian churches, and its faultlines in many instances reflect Christian divisions. The Christian understanding of the human person has until recently undergirded much of the common legal and moral framework, along with the inheritance of Roman law and Greek philosophy (both mediated through the Christian churches). But Europe has also undergone a massive secularisation, and even though the character of secularisation varies across the continent, the mainline churches are all suffering from decline. Migration has brought into Europe a significant presence of Christians from non-European cultures and members of other faiths; this can also be a cause of tension.