In some denominations they are called "Ministers of Word and Sacrament", and in others they are called "Teaching Elders". Ministers called to a particular congregation are called "pastors", and serve a function analogous to clergy in other denominations. (Because ruling elders are often ordained in a fashion nearly identical to teaching elders, the distinction between lay and clergy is not as clear under the Presbyterian system as in others). The terms 'lay' and 'clergy' are not properly used in presbyterian polity.