Actually, Popes have resigned/retired before. This is from a RCC website:
Pope can step down if he wants to - and he wouldn’t be the first
Pope Benedict IX who abdicated in favour of his godfather, who became Pope Gregory VI, in 1045
By Dr Joe Morley
If - contrary to popular belief that a pope cannot resign - Pope John Paul II decided to resign, he would join a long line of popes whose pontificates were interrupted or curtailed by a variety of causes other than natural death.
A pope can resign.
Canon Law 332:2 states: “Should it happen that the Roman Pontiff resigns from his office, it is required for validity that the resignation be freely made and properly manifested; but it is not necessary that it be accepted by anyone.”
The records show that four popes, Pontian (Pontianus), St Silverius, St Celestine V and Gregory XII resigned or abdicated.
Benedict IX resigned but was reinstated.
And John XVIII is also thought to have resigned.
The pontificates of 26 other popes were interrupted or curtailed by deposition, imprisonment, death while imprisoned, murder or by exile.
The first to resign - St Pontianus - was elected in 230, then arrested by Emperor Maximinius in 235 and exiled to Sardinia. Expecting never to be released, Pontianus resigned on September 28, 235, and died in captivity the same year.
Next was St Silverius who reigned from June 1, 536 to November 11, 537. Emperor Justinian deposed him in March 537 and sent him into exile. Recalled to Rome to stand trial for alleged treason and pressed by Pope Vigilius who had succeeded him, Silverius was again exiled to Palmaria, where, under threats, he resigned on November 11. He died in captivity on December 2, 537.
Third to resign (and the one usually quoted as being the only pope to resign) was the aged monk Peter Morrone, who became St Celestine V. Pope Nicholas IV died on April 4, 1292, but the cardinals had still not agreed on the election of a successor more than two years later. Peter, then 85, and living as a Benedictine hermit, was unwillingly taken to L’Aquilia in central Italy where, on August 29, 1294, he was consecrated as Bishop of Rome (Pope), taking the name Celestine V.
Because of turmoil in Rome, Celestine never resided there.
Dominated by King Charles of Sicily and Naples, Celestine went to Naples. He was unable to cope with the burdens of office and, under pressure from Cardinal Caetani, who himself aspired to the throne of Peter, Celestine resigned on December 13, 1294, after only three-and-a-half months in office.
Caetani succeeded him as Boniface VIII.
Finally, the last officially recognised resignation was that of Gregory XII.
As successor to the legitimate popes Urban VI (1378-89), Boniface IX (1389-1404) and Innocent VII (1404-06) during the Great Schism (1378-1417), Gregory was elected on November 30, 1406.
Along with the anti-pope* Benedict XIII, Gregory was ‘deposed’ as a schismatic by the Council of Pisa on June 5, 1409.
However, at the Council of Constance (1414-18), Gregory agreed to resign, provided he was allowed to convoke the council which had been called by Emperor Sigismund and which in 1415 had deposed the anti-pope John (XXIII), who had been elected by the Pisan council in 1410.
The council agreed and, on July 4, 1415, Gregory’s bull convoking the council and announcing his resignation, was read. The council elected Martin V on November 21, 1417, thus ending the 39 years of schism.
Gregory XII was the last pope to resign officially.
Two other popes, John XVIII (1003-1009) and Benedict IX (1032-1048), are believed to have abdicated.
John XVIII, about whose reign very little is known, was elected on December 25, 1003, and may have resigned under pressure just before he died in late June or early July 1009.
Benedict IX became pope on October 21, 1032, and (the only pope to have done so) held the office on three occasions. Deposed in September 1044, he fled from Rome. He ex-communicated the anti-pope Sylvester II (III), who had succeeded him, and reclaimed the papacy in March 1045. But in May he abdicated in favour of his godfather, who became Pope Gregory VI.
At the Synod of Sutri (near Rome) called by Emperor Henry III, Gregory and Sylvester were deposed on December 20; Benedict was formally deposed at a synod in Rome on December 24.
They were all succeeded by Clement II (1046-1047), who died suddenly in August 1047.
Benedict was reinstated as pope on November 8, 1047. He remained in office until July 16, 1048, when he was again deposed by Emperor Henry III.
Still claiming his right to the papacy, Benedict retired to his birthplace. He was succeeded by Damasus II and St Leo IX.
At a synod in the Lateran in April 1049, Benedict was summoned to answer charges of simony. He did not respond and was excommunicated. He died seven years later.
Two popes, Pius VI and Pius VII, suffered at the hands of Napoleon. Pius VI (February 15, 1775-August 29, 1799) was arrested on Napoleon’s orders and taken to France, where he died. His reign was one of the longest in history.
Pius VII (March 14, 1800-July 20, 1823), also arrested by Napoleon, was taken to Paris a virtual prisoner, and remained there until the downfall of Napoleon in 1814.
On September 2, 1870, Italian troops occupied Rome and Pope Pius IX, no longer possessing Papal States, declared himself “the Prisoner of the Vatican”, which he remained until his death on February 7, 1878.
Succeeding popes until Paul VI continued the role of ‘Prisoner of the Vatican’.
*Anti-popes are so called because they were elected to office in opposition to popes held by others to be canonically chosen.
www.catholicweekly.com.au/02/jun/2/19.htmlIronically, if you do a search some of the sites claim that it's difficult to tell who exactly resigned because the records from the first few hundred years are "in such disarray." Tell the truth - THEY DON'T EXIST BECAUSE THERE WAS NO RCC UNTIL CONSTANTINE STARTED IT!