58.

 Let no one ranked among Laymen administer the divine Mysteries to himself, when a Bishop, or a Presbyter, or a Deacon is present. Let anyone that dares to do any such thing he excommunicated for a week on the ground that he is doing contrary to what has been ordered. Thus will he be instructively persuaded “not to think contrary to what he ought to think” (Rom. 12:3).

Interpretation.

For a layman himself to partake of the divine Mysteries by himself, i.e., by helping himself thereto, without there being any need of doing so (when a Bishop, or Presbyter, or Deacon, that is to say, is not present, according to Zonaras), is a work of presumption, and whoever does it is usurping unlawfully the office of the priesthood. For this is the function of priests, not of laymen. So for this reason the present Canon excommunicates from the Church for a week anyone that dares to do this, in order to teach him not to think in excess of what he ought to think according to the Apostle.[182]