The Church of Scotland (Scots: The Scots Kirk, Scottish Gaelic: Eaglais na h-Alba), known informally by its Scots language name, the Kirk, is the national church in Scotland. It is Protestant and Presbyterian. Its longstanding decision to respect "liberty of opinion on matters not affecting the substance of the faith" means it is relatively tolerant of a variety of theological positions, including those who would term themselves conservative and liberal in their doctrine, ethics and interpretation of Scripture.