From my vantage point, it was hard to gauge exactly how many people filled the enormous Revolution Square in Havana, but their enthusiasm was clear to everyone watching.
The Pope was greeted by thousands in good voice and high spirits, despite the suffocating Caribbean heat.
It was a rare sight - the iconography of revolution such as the huge cast-iron Che Guevara mural juxtaposed against the images of religion, including a vast huge picture of Jesus Christ. Or Raul Castro embracing Pope Francis.
Once again, it felt like evidence that times are changing on the communist island.
In terms of his homily, the Pope discussed ideas of brotherhood and unity but the more overt political message was aimed not at Cuba, but Colombia.
He urged the Colombian government and the left-wing Farc rebel group to persevere with the talks being held in Havana, saying they could not allow "another failure on the path of peace and reconciliation".
Grey line
Cuba's President Raul Castro, who is not a practising Catholic, attended, as did Cristina Fernandez de Kirchner, president of the Pope's native Argentina.
The Pope praised improved co-operation between the Cuban government and the Church on Saturday, but called for the Church in Cuba to have "the freedom and the means" to pursue its mission.
Both his predecessors, Pope John Paul II and Pope Benedict XVI, visited the island during their papacy.
Pope Francis is due to fly to Washington on Tuesday. He has been credited with helping the recent thaw in diplomatic ties between Cuba and the US.
After his arrival on Saturday, he hailed improving ties between the two countries as "an example of reconciliation for the whole world".
But he also urged both Cuba and the US to "persevere on the path" of detente.