From the very beginning of the Church, the martyrs were held in high esteem because they so perfectly lived their life for Christ, even to death. At first, it was tradition to gather around a martyr's tomb, especially in the catacombs, to celebrate the Eucharist. The Eucharist memorializes Jesus' self-sacrifice, thus it is fitting also to remember the martyrs' self sacrifice through the Eucharistic celebration.
Eventually, when possible, churches were built over the tombs of saints (St. Peter's in Rome is a well-known example). When building over a martyr's tomb was not possible, relics of the saints would be inbedded in an altar stone. Today, when possible, relics are still placed beneath an altar.
Saints are those who have lived a life of virtue and serve as a model for all of us to live the Gospel as they did. The relics are visible, tangible signs to us of their life and our own call to a live a life of holiness and self-sacrifice. Those who have gone to heaven before us intercede for us.

The Maria Stein Shrine of the Holy Relics houses over 1,000 relics of the Saints and the True Cross. 95% of the relics in the Maria Stein collection are First Class. The first relics were brought to the area by Fr. Francis de Sales Brunner, who founded most of the local churches and convents, bringing priests, brothers and sisters of the Precious Blood communities to America. After his death, the significant collection of his relics, including a Calendar of Relics, and the bodily remains of St. Victoria, were under the care of the Sisters. In 1872, Fr. J. M. Garner, a priest from Milwaukee, acquired 175 relics for safekeeping in the New World. When he brought them to America, his original intent was to have a kind of traveling exhibit. But the faithful wanted them kept together, and suggested finding a permanent place for the collection. When he heard about the many relics under the care of the Sisters of the Precious Blood, he approached the Sisters, and together they gathered all of the relics into one collection, and we became the Shrine of the Holy Relics in 1875.

The glass altar houses the collection of relics of Fr. Brunner. The main altar is home for the relics brought to Maria Stein by Fr. Gartner. The main altar’s central focus is a Relic of the True Cross. In the former tabernacle of this altar there are two relics which can be taken down and prayed with: a second relic of the True Cross, and one of St. Peregrine, the patron saint of those with cancer. A highlight of the Sorrowful Mother altar, on the left, is the relics of St. Ursula and Companions, in the base of the altar. In the same area of the Sacred Heart altar is the remains of St. Victoria, a martyr of the early Church (c.304), covered with wax. On the east wall, opposite the glass altar of Fr. Brunner’s collection, are two cases: St. Gaspar case and the Memorial case, both housing more recently acquired relics arranged in clusters of interest.

The process of becoming a Saint does not usually begin until five years after his or her death, which allows time for the person's virtuous and saintly reputation to grow. The information on their life and virtues as well as public and private writings are collected and reviewed. Once the approved process has begun, the individual is called a “Servant of God.” Before one can become a Saint, two miracles must be attributed to the person and verified by proper authorities, or proof of martyrdom and one miracle. When the first miracle, or martyrdom, is approved, the person is then called "Blessed." Once beatified, their feast is established and their relics can be venerated. When a second miracle is approved, then the person will be canonized thus becoming publicly recognized as a Saint of the Catholic Church.