Italian daily Corriere della Sera published a letter to the editor from Francis, signed and dated March 14 from Rome's Gemelli hospital where the 88-year-old pontiff has been treated since February 14 for a complex lung infection and double pneumonia.
In it, Francis renewed his call for diplomacy and international organisations to find a "new vitality and credibility".
And he said his own illness had also helped make some things clearer to him, including the "absurdity of war".
"Human fragility has the power to make us more lucid about what endures and what passes, what brings life and what kills," he wrote.
Responding to a letter from the newspaper's editor-in-chief, Luciano Fontana, Francis also urged him and all those in the media to "feel the full importance of words".
"They are never just words: they are facts that shape human environments. They can connect or divide, serve the truth or use it for other ends," he wrote.
"We must disarm words, to disarm minds and disarm the earth."
The letter was published as Francis registered slight improvements in his treatment and as the Vatican No.2, Cardinal Pietro Parolin, shot down any suggestion the Pope might resign.
"Absolutely no," Parolin told journalists on Monday.
Parolin has visited Francis twice during his hospitalisation and said he found Francis better then than his first visit on February 25.
Francis is now able to spend some time during the day off high flows of oxygen and use just ordinary supplemental oxygen delivered by a nasal tube, the Holy See media office said.
Doctors are also trying to cut back on the amount of time he uses a non-invasive mechanical ventilation mask at night, to force his lungs to work more.
While those amount to "slight improvements", the Vatican is not yet providing any timetable on when he might be released.
That said, Buckingham Palace announced on Monday that King Charles III was scheduled to meet Francis on April 8 at the Vatican.
Such state visits are always closely organised with Parolin's office, suggesting that the Holy See believed the Pope would be back home by then, barring any setbacks.
The developments came as the Vatican released some details on the first photograph of Francis released since his hospitalisation.
The image, taken on Sunday from behind, showed Francis sitting in his wheelchair in his private chapel in prayer without any sign of nasal tubes.
The photo followed an audio message Francis recorded on March 6 in which he thanked people for their prayers, his voice soft and laboured.
