Pope Francis encouraged Christians to remember their baptism with "joy," as he reflected on the role of Jesus Christ's baptism by John the Baptist in God's saving mission for humanity.

The Pope said the opening of the heavens when John the Baptist baptized Jesus "ended the time of the 'closed heavens' which indicate the separation between God and man, the consequence of sin."

"The open heavens indicate that God gave his grace for the earth to bear fruit. So the earth has become the dwelling of God among men, and each of us has the opportunity to meet the Son of God, experiencing all his love and infinite mercy," he told tens of thousands of people gathered in St. Peter's Square for the Sunday Angelus Jan. 11.

"Sin alienates us from God and breaks the link between Earth and Heaven, thus determining our misery and failure of our lives," he added.

Sunday marked the Feast of the Baptism of the Lord. Pope Francis reflected on the day's Mass readings, which included a reading from the Gospel of Mark's first chapter about Jesus' baptism in the Jordan River and the descent of the Holy Spirit.

When God's voice proclaims "You are my beloved son, with you I am well pleased," the Pope explained, "the Father's voice proclaims the mystery that lurks in the Man baptized by John the Baptist."

The descent of the Holy Spirit allows Jesus Christ to begin his mission of mankind's salvation.

"Remember this: pray often to the Holy Spirit because he helps us, he gives us strength, he gives us inspiration and helps us move forward!" the Pope exhorted.

Pope Francis said the Holy Spirit encourages the spread of the Gospel "to the ends of the earth and of society."

He lamented the existence of Christians and communities who are "deaf" to the voice of the Holy Spirit and are also becoming "mute." He described them as those who "do not speak and do not evangelize."

The Pope suggested that the Holy Spirit is "the Great Forgotten One in our prayers." Christians often pray to Jesus and to God the Father, but not so frequently to the Holy Spirit.

"And we need to ask for his help, his strength, his inspiration. The Holy Spirit who animated entirely the life and ministry of Jesus is the same Spirit who now leads the Christian life."

Pope Francis encouraged Christians to place their lives as Christians "under the action of the Holy Spirit" as well as to place under the Holy Spirit their baptismal mission to find "the apostolic courage necessary to overcome easy, worldly accommodations."

He also stressed that Jesus is really present in the sacraments, especially the Eucharist.

"We can recognize him in the faces of our brothers, especially the poor, the sick, the imprisoned, the refugees: they are living flesh of the suffering Christ and the visible image of the invisible God."

After the Angelus prayers, Pope Francis encouraged prayers for the imminent start of his latest apostolic voyages.

"This evening I will depart on an apostolic visit to Sri Lanka and the Philippines. Thanks for your prayers in this shared endeavor, thanks very much! And I ask you please to accompany me with prayers and I also ask the Sri Lankans and Filipinos who are here at Rome who have specially prayed for me for this visit," he said.

Pope Francis concluded by asking the faithful to "remember with joy" their baptism.

In a morning Mass at Vatican City's Sistine Chapel, the Pope baptized 33 babies.