BOGOTÁ, Colombia — The memory of the land mine that tore off the leg of Helena González’s nephew years ago is still fresh.

Ms. González, 25, has spent much of her life fearing more attacks by Colombia’s Marxist rebels against her family. And last year, when given the chance to vote on a peace agreement to end a half-century of conflict, she joined the majority of Colombians in voting against the deal.

“The pope may forgive them,” Ms. González said, coming out of church in the capital, Bogotá, this week. “But in my heart I don’t forgive them. I am still reconciling it all.”

As Pope Francis arrived in Colombia on Wednesday for a six-day visit, the challenge before the leader of the Roman Catholic Church was clear: nudging the country, torn apart by 52 years of war, toward a peace with former guerrillas that remains controversial in the eyes of many of the war’s victims.