Cyclopedia of Biblical, Theological and Ecclesiastical Literature
a term used by certain 17th-century Anglican writers for the fixed or movable rail placed on each side of the entrance of the sanctuary to support the communicants when they knelt to receive the Lord's body and blood.
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McClintock, John. Strong, James. Entry for 'Septum'. Cyclopedia of Biblical, Theological and Ecclesiastical Literature. https://www.studylight.org/encyclopedias/eng/tce/s/septum.html. Harper & Brothers. New York. 1870.