The worrying signs had been coming for a long time.
But the graphic confirmation occurred on the trip that was to take the Pope to Malta on April 2.
As usual, Francisco boarded the last one, when all the journalists and the entourage that accompanies him were already on the plane.
This time, however, he had to do it with the help of a lateral forklift to avoid the pain in his knee caused by the effort of climbing the stairs of the ship.
On the return trip he himself explained it this way to questions from journalists: “My health is a bit capricious.
I have a knee problem, which causes locomotor problems.
But it improves, at least now I can walk.
Two weeks ago I couldn't even do that.
It's kind of slow.
Let's see if he goes back, but at this age you don't know how the game will end.
Let's hope it goes well."
The reality is that the problems - which, according to the only information, could be due to knee pain, a vague term for knee pain caused by many factors - have not improved since then.
The inflammation he suffers from, which he reported for the first time on January 17 at a General Audience, prevents him from sitting down and getting up easily and from climbing steps.
Francisco has again suspended his schedule on Tuesday on medical advice, due to the same pain in his right knee.
And the Vatican communication office has referred to it for the first time.
"Due to knee pain and on medical advice, Pope Francis has interrupted the activities planned for today, including his participation in the meeting of the Council of Cardinals, of which a new session began today," he reported in a brief The Vatican press office reported.
It is the same circumstance that also disqualified him last Friday to receive the Argentine Foreign Minister, Santiago Cafiero, and to officiate important ceremonies.
The Pope, moreover, was also unable to celebrate, as planned, the Sunday mass dedicated to Divine Mercy.
Archbishop Rino Fisichella did it instead.
He was also unable to officiate the Easter Vigil on Holy Saturday in St. Peter's Basilica, which was presided over by Cardinal Giovanni Battista Re, dean of the College of Cardinals.
In these ceremonies, Francisco remained seated in a chair and only delivered the homily.
The Pope did preside over the celebration of the Passion of Christ in St. Peter's Basilica in the Vatican, but he did not lie down on the floor of the temple to pray, as is traditionally done.
The Vatican maintains confirmed Francis' presence at Wednesday's general audience in St. Peter's Square.
But the intense pain suffered by the Pontiff, whose physical suffering is sometimes visible on his face, open some unknowns about his busy schedule.
Especially about the three demanding trips scheduled for the months of June and July.
Francis planned to visit Lebanon and perhaps Jordan on June 12.
This trip could include, as he himself announced, a meeting with Patriarch Kirill of Moscow.
In addition, in July the trip to the Democratic Republic of the Congo and South Sudan is already confirmed and it is very likely that he will also travel to Canada, complying with the invitation of the indigenous groups that visited him just a month ago.
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