Scientists have poured over the Shroud of Turin for decades, and even recently it has been reported that the shroud can be dated to 2,000 years ago.
Yet, does that mean Catholics are required to believe in its authenticity?
Belief in the Shroud's authenticity
Belief in the authenticity of the Shroud of Turin is not required by the Church, though many have had their faith bolstered by its existence.
Mark Armstrong wrote for Catholic Exchange an article in which he quotes both St. John Paul II and Pope Benedict XVI and their views of the Shroud:
Skeptics claim the cloth is a clever medieval forgery and yet it was lovingly referred to by the late Holy Father John Paul II, “as an image of God’s love as well as of human sin.” Although Pope Benedict, as Cardinal Ratzinger, was very cautious about giving Church approval to apparitions or private revelations, he placed the Shroud in a different category when he wrote about it his book, The Spirit of the Liturgy. Pope Benedict wrote that the Shroud was “a truly mysterious image, which no human artistry was capable of producing. In some inexplicable way, it appeared imprinted upon cloth and claimed to show the true face of Christ, the crucified and risen Lord.”
While not a "private revelation," such as an apparition of Mary, accepting or rejecting the Shroud of Turin as a Catholic would fall under similar principles.
The Catechism of the Catholic Church explains that private revelations do not belong to the deposit of faith:
Throughout the ages, there have been so-called "private" revelations, some of which have been recognized by the authority of the Church. They do not belong, however, to the deposit of faith. It is not their role to improve or complete Christ's definitive Revelation, but to help live more fully by it in a certain period of history. Guided by the Magisterium of the Church, the sensus fidelium knows how to discern and welcome in these revelations whatever constitutes an authentic call of Christ or his saints to the Church.
Public revelation stopped with the activity of the apostles and since then, the Church has been unpacking and mining the depths of the Bible.
Our own souls will be judged, not by belief in a private revelation, but by belief in the public revelation contained in the Bible, authentically interpreted by the Catholic Church.
Private revelations, or relics of the Passion, such as the Shroud of Turin, may help us along the journey of our lives and can lead us to a more intimate relationship with God. However, Catholics are not obligated to believe in the authenticity of the Shroud of Turin or any similar relics. Similarly, we are not obligated to believe in private revelations, even those that have been approved by the Church, such as Fatima or Lourdes.
The Church helps us by discerning if a private revelation is in accord with what Christ revealed, and thus we are free to believe in it; on the other hand, the Church can determine that a private revelation is not supernatural in origin because it contradicts with Christ's definitive Revelation.
