The names still borne by two of the swords reflect the fierce controversies of the Middle Ages between the Pope and the Emperors, the Pope claiming the right to invest the ruler with his temporal authority.  From this dispute came the Doctrine of the Two Swords — with the first sword the symbol of temporal power and the second sword representing the spiritual authority of the Church.  The popes claimed the right to invest the Emperor and other rulers with both swords by the hands of the prelates of the Church.

  Two of the swords in the English regalia borne at the coronation of Queen Elizabeth II and displayed in the Jewel House are still known, therefore, as the Sword of Justice to the Spirituality and the Sword of Justice to the Temporality, although the names had long ago come to have less controversial meanings in this country.

Brian Barker.  The Symbols of Sovereignty, David and Charles: North Pomfret, VT, 1979.