At St. Peter's Basilica in Vatican City, Francis lamented the horrors generated by war and hatred, delivering an Easter Sunday message that decried the "latest vile" attack in Syria - a bombing Saturday that killed more than a hundred people.
Easter has special importance for Christians because it recalls the resurrection of Jesus Christ after his crucifixion.
More police vans and army vehicles than usual were positioned at the entrances to the Vatican area and the faithful were stopped at several check points leading into the square, which was decorated with 35,000 flowers and trees.
Those ordinary, human gestures, sustained by faith in the Risen Lord, the Pope said, will be transformed by the Spirit and take on new strength to reach into every heart, freeing us from wretchedness and bringing hope to the suffering and oppressed.
"Nobody asks us: "But, are you happy with all that's happening in the world?' Are you willing to go forward", carrying a cross, as Jesus did? Today we can proclaim: "The Good Shepherd has risen, who laid down his life for his sheep, and willingly died for his flock, alleluia" (Roman Missal, IV Sunday of Easter, Communion antiphon).
As he finished his unscripted homily, heavy rain started.
He reflected on suffering including wars, oppressive regimes, human trafficking, corruption, starvation and domestic violence in an impromptu homily during Mass in St Peter's Square and in his formal "Urbi et Orbi" Easter message delivered from St Peter's Basilica. The Western Christian church follows the Gregorian calendar, while the Eastern Orthodox uses the older Julian calendar, so the two Easters are often weeks apart. The Holy Fire ceremony is part.
On Friday, the pontiff led the Via Crucis (Way of the Cross) procession at the Colosseum.
Tens of thousands of Catholics underwent massive security checks to gather in the Vatican for Pope Francis' Easter Sunday Mass.
Sunday also marks the 90th birthday of Francis' predecessor, Pope Emeritus Benedict XVI.