Inside the chapel of Our Lady of Hope at Sing Sing Prison, inmates sitting in the penitentiary's chapel pews were stunned by what they had received from Pope Francis.

Denis Martinez, a convicted felon of eleven years serving time at Sing Sing, sent an original drawing of three crucifixes on Calvary as a gift to Pope Francis.

Other inmates sent messages along with the drawing to the Pope, as a symbol of their respect for him.

Much to their surprise, the inmates at Sing Sing received a gift in return from the Holy Father, who sent Martinez and his fellow prisoners a rosary, blessed holy cards, and a promise to keep them in his prayers.

"I can't believe one of my drawings was given to the pope, while I'm here, trapped," Martinez stated in a Dec. 15 interview with the New York Times. "His message is one I believe in, one of social justice. Those of us who've been on the floor, like I've been on the bottom, we know about the struggle."

Although Martinez admitted that his own faith was at times shaky, he and the other inmates who unite in the prison's chapel in prayer feel a special affection towards the Pope.

The gift of the drawing was an idea prompted by one of the prison's volunteers, Betty Woodward. In her meetings with the prisoners who attend Mass and Bible studies, she often spoke about Pope Francis and his message of love.

"They were blown away by the fact that one of the first things Pope Francis did was go to a prison and wash the feet of prisoners on Holy Thursday," Woodward told the New York Times.

"My personal reflection on this is that Pope Francis is like a father figure to them. He is not a distant person. He is warm, understands things and talks about mercy, love and not judging. These guys devour that message."

Using a fingerprint ink pad to create the drawing, Martinez drew the three crucifixes on Calvary reflecting in the eye of Christ crucified.

"It's a reflection in the pupil of the crucified Christ in the middle with two smaller crosses for the good thief and the bad thief," Woodward said.

"In Denis's mind you have your choice: You can be the good thief or the bad thief. You can be bad, but become good."

During an October audience, Woodward personally presented Martinez' drawing and the other inmates' messages to Pope Francis. After returning from the audience, Woodward presented the men with the gifts that the Holy Father had sent in return.

Additionally, Pope Francis gave Martinez a portrait of himself. Upon receiving the picture, Martinez's eyes filled with tears.

"This is the most beautiful gift I have received in here," Martinez stated, adding, "I'm not the best Catholic, but my mother tried."

"Even if you doubt, you can take something from the pope's message. You can find yourself in the bottom of the pit, but you can still hear his message and say 'alleluia.'"