The Proper Numbers
The proper numbers tell the celebrant which prayer in the service book is the proper preface for the Communion service on that day. The Roman Catholic Church and the Anglican Church of Canada, among some others, use the proper numbers in parentheses. The proper numbers are also an easy way to refer to the readings.
Many denominations don’t have a service book with proper prefaces, in which case the celebrant can compose and pray a brief prayer that connects the theme of the lectionary readings to Communion.
The Alternative Readings
The only difference between Alternative One and Alternative Two is the readings from the Old Testament. “Alternative One” readings are for general use. They follow a more-or-less continous story line in the Old Testament that is generally not related to the topic of the New Testament readings. “Alternative Two” readings tie the Old Testament readings thematically with the New Testament Readings. They are used primarily by Roman Catholics, Lutherans, and Anglicans.