usades. The crusading-indulgences, granted at first only to
those who actually went to the Holy War, subsequently to those
also who contributed to the expense of the expedition, were
virtually the acceptance of this work as a substitute for any
penance which the Church might otherwise require. As zeal for the
Crusades began to wane, the indulgences were used more and more
freely to stimulate lagging interest; their number was greatly
increased, and those who purchased the indulgences with money far
outnumbered those who actually took the Cross. Failing in their
purpose as an incentive to enlistment in the crusading armies,
they showed their value as a source of income, and from the
beginning of the XIV. Century the sale of indulgences became a
regular business.

About the lame time a new kind of indulgence arose to take the
place of the now somewhat antiquated crusading-indulgence. This
was the Jubilee-indulgence, and had its origin in the Jubilee of
1300. By the Bull _Antiquorum Habet Fide_, Boniface VIII. granted
to all who would visit the shrines of the Apostles in Rome during
the year 1300 and during each succeeding centennial year, a
plenary indulgence.[14] Little by little it became the custom to
increase the number of these Jubilee-indulgences. Once in a
hundred years was not often enough for Christians to have a
chance for plenary forgiveness, and at last, unwilling to deprive
of the privileges of the Jubilee those who were kept away from
Rome, the popes came to grant the same plenary indulgence to all
who would make certain contributions to the papal treasury.[15]

Meanwhile the Sacrament of Penance had become an integral part of
the Roman sacramental system, and had replaced the earlier
penitential discipline as the means by which the Church granted
Christians forgiveness for sins committed after baptism. The
scholastic theologians had busied themselves with the theory of
this Sacrament. They distinguished between its "material," its
"form" and its "effect." The "form" of the Sacrament was the
absolution: its "effect," the forgiveness of sins; Its
"material," three acts of the penitent: "confession,"
"contrition," and "satisfaction." "Confession" must be by word of
mouth, and must include all the sins which the sinner could
remember to have committed; "contrition" must be sincere sorrow
of the heart, and must include the purpose henceforth to avoid
sin; "satisfaction" must be made by works prescribed by th