In 1842, use of the ring and wax seal were replaced by a stamp, but each pope still receives a unique Ring of the Fisherman at the start of his papacy, which is then destroyed soon after his death.
In the early 20th century, St. Pius X connected a partial indulgence to kissing the Fisherman's Ring.
The custom started to change with St. Paul VI in the last decades of the 20th century, when he eliminated other forms of showing papal obedience and subservience, such as kissing the pope's foot, shoulder, and cheek, Regoli explained.
Fr. Johannes Grohe, a professor of Church history at the Pontifical University of the Holy Cross, told CNA that to greet a bishop with a kiss of his ring is a sign of his episcopal dignity and is still "quite widespread."
In the past, "this gesture was accompanied by a bow of the head or a knee bend," he said, and while "kissing the episcopal ring in an official greeting is still in use, to bend the knee not so much."
Pope Francis, he continued, "seems to be against it. Sometimes he allows it, sometimes he denies it (even in an apparent way)."
Regoli said that with Francis "there is a further sensibility, different from his predecessors, so we tend to further simplify the ceremonial by omitting the greeting of genuflection towards him."
According to Grohe, "there is in [Pope Francis] an attitude contrary to everything that could recall court customs," and "certainly," he added, "some customs in ceremonies and pontifical audiences have a long tradition and therefore also have the form of other time periods."
Hannah Brockhaus is Catholic News Agency's senior Rome correspondent. She grew up in Omaha, Nebraska, and has a degree in English from Truman State University in Missouri.