text: Use and design In the service of benediction, (the priest blesses the people with the Eucharist displayed in the monstrance). This blessing differs from the priest's blessing, as it is seen to be the blessing by Christ rather than that of the individual priest. The exposition of the monstrance during Benediction is traditionally accompanied by chanting or singing of the hymn Tantum Ergo.
  Monstrances are usually elaborate in design; most are carried by the priest. Others may be much larger fixed constructions, typically for displaying the host in a special side chapel, often called the "Chapel of the Blessed Sacrament". For portable designs, the preferred form is a sunburst on a stand, usually topped by a cross.
  Before the Council of Trent, the most common design was the tower.  The sun design would come to dominate the shape of modern monstrances after it became clear that the ostensorium could be better adapted to the object of drawing all eyes to the Sacred Host itself by making the transparent portion of the vessel just of the size required, and surrounded, like the sun, with rays. Monstrances of this shape, dating from the fifteenth century, are also not uncommon, and for several hundred years past this has been by far the commonest form in practical use.