Some Presbyterian traditions adopt only the Westminster Confession of Faith as the doctrinal standard to which teaching elders are required to subscribe, in contrast to the Larger and Shorter catechisms, which are approved for use in instruction. Many Presbyterian denominations, especially in North America, have adopted all of the Westminster Standards as their standard of doctrine which is subordinate to the Bible. These documents are Calvinistic in their doctrinal orientation. The Presbyterian Church in Canada retains the Westminster Confession of Faith in its original form, while admitting the historical period in which it was written should be understood when it is read.