This suncatcher
window is centered on the monogram of the name of Jesus. The monogram became more popular after
the twelfth century when St. Bernard insisted much on devotion to the Holy Name
of Jesus, and the fourteenth, when the founder of the Jesuati, Blessed John
Colombini (d. 1367), usually wore it on his breast. Towards the close of the
Middle Ages IHS became a symbol, quite like the chi-rho in the Constantinian period.
Sometimes above the H appears a cross and underneath three nails, while the
whole figure is surrounded by rays. IHS became the accepted iconographical
characteristic of St. Vincent Ferrer (d. 1419) and of St. Bernardine of Siena
(d. 1444). The latter holy missionary, at the end of his sermons, was wont to
exhibit this monogram devoutly to his audience, for which some blamed him; he
was even called before Martin V. St. Ignatius of Loyola adopted the monogram in
his seal as general of the Society of Jesus (1541), and thus it became the
emblem of his institute.