Pope Francis officially announced the date he would venerate the shrine of Our Lady of Guadalupe in Mexico during his homily for the Marian feast at the Vatican.

Speaking at the Dec. 12 Mass in St. Peter's Basilica, the Pope said he will venerate the shrine on Feb. 13, 2016, where he will pray that Christian communities may be "oases and sources of mercy," and a witness to charity "that does not allow exclusions."

The Pope will travel to Mexico from Feb. 12-18, the Vatican announced Saturday. During a recent press briefing, Francis said his next trip would likely be to Mexico, although the details had not been finalized.

In his homily for Mass celebrated for the feast of Our Lady of Guadalupe, Pope Francis asked for Mary's intercession in cultivating mercy during this Jubilee year, and entrusting the sufferings and joys of the people of the Americas to her care.

"God delights and pleases especially in Mary," the Pope said, speaking in his native Spanish. "She has experienced Divine mercy, and welcomed the very source of this mercy in her womb: Jesus Christ."

"She who has always lived intimately united with her Son, knows better than anyone what he wants: that all men be saved, and God's tenderness and consolation will not fail anyone."

Pope Francis entrusted to Mary the "sufferings and joys of people throughout the Americas," who love her as their mother,  under the title of Our Lady of Guadalupe.

"We ask (Mary) that this jubilee year will be a cultivation of merciful love in the hearts of individuals, families, and nations."

Pope Francis also appealed to Mary that "we may become merciful, and that Christian communities may be oases and sources of mercy, witnessed a charity that does not allow exclusions."

"I beg her to guide the footsteps of the American people, a pilgrim people looking for the Mother of mercy, and ask her to reveal to us her Son, Jesus."

Veneration of Our Lady of Guadalupe goes back to the 16th century, and surrounds a miraculous image of Mary left on a tilma, made from a piece of poor-quality cactus cloth.  

As the story goes, a "Lady from Heaven" appeared to Saint Juan Diego, a poor Indian from Tepeyac, on a hill northwest of Mexico City. Over the course of a series of apparitions in 1531, the Woman, who identified herself as the Mother of the True God, instructed Juan Diego to have the bishop build a church on the site.

As a sign, the now-famous image of Our Lady of Guadalupe was imprinted miraculously on his tilma. Both the image and the tilma remain intact after more than 470 years.

Pope Francis centered much of his homily Saturday on God's mercy toward sinners.

God's loves us with "gratuitous love," and expects nothing in return, the pontiff said. God's merciful love, which is synthesized in the Gospel message and the faith of the Church, is his most "striking" attribute.

Pope Francis explained that the word "mercy" is derived from the words "misery" and "heart."

"The heart indicates the capacity to love," he said. "Mercy is love which embraces the misery of the human person. It is a love that 'feels' our poverty as its own."

"The Word became flesh" out of a desire to share our frailties, the Pope said. "He wanted to experience our human condition, to carry upon the cross with all the pain of human existence."

"Such is the depth of compassion and mercy," the Pope said. There is no sin that can take away God's "merciful closeness," or prevent him "from unleashing the grace of conversion," provided we ask for it, he noted.  

Indeed, sin reveals the radiance of the love of God, who sacrificed his own Son in order to ransom the enslaved. Citing the words of St. Paul, who says "The Lord is near," the Pope assured those present that there is no reason to worry.

"The greatest mercy lies in His being in our midst," he said. "Walking with us, he shows us the path of love, lifts us up from our falls, sustains us in our weariness, accompanies us in all circumstances of our existence."

The Pope cited Paul's letter to the Philippians, which says "the peace of God, which passes all understanding, will keep your hearts and your minds in Christ Jesus."

"This is the source of our peaceful and happy life," the Pope said. "Nothing can steal this peace and joy, despite the sufferings and trials of life.

In off-script remarks, the pontiff added: "The Lord, with his tenderness, opens us with his heart, opens us with his love. The Lord is allergic to rigidity."

Pope Francis invited the faithful to cultivate this sense mercy, peace, and hope in the journey through the liturgical season of Advent, illuminated by the light of the recently-begun Jubilee of Mercy.