Vatican City, May 24, 2015 / 10:14 am (CNA/EWTN News).- Pope Francis used Sunday's feast of Pentecost – the descent of the Holy Spirit – as an occasion to remind Christians of their duty to care for and respect the earth.

“The Holy Spirit whom Christ sent from the Father, and the Creator Spirit who gives life to all things, are one and the same,” the Pope said.

“Respect for creation, then, is a requirement of our faith: the 'garden' in which we live is not entrusted to us to be exploited, but rather to be cultivated and tended with respect.”

Pope Francis, dressed in red vestments traditional for the solemnity of Pentecost, made these remarks during Mass in Saint Peter’s Basilica.

Reflecting on Adam, who himself was “formed from the earth,” the pontiff explained, this respect for the earth is only possible when man is renewed by the Holy Spirit, and “reformed by the Father on the model of Christ, the new Adam.”

In this way, “we will indeed be able to experience the freedom of the sons and daughters, in harmony with all creation.”

These remarks about man’s responsibility to care for the earth comes ahead of the Pope’s upcoming encyclical on environmental degradation and the global effects of climate change on the poor.

Expected to be published in mid-late June, the document has already been written and is currently being translated.

Reflecting on the day’s readings for the feast of Pentecost, Pope Francis cited the second letter Saint Paul to the Galatians, comparing those who allow the Holy Spirit into their lives with those who close themselves off to the Spirit through selfishness, “rigid legalism,” neglecting Jesus’ teachings, and so on.

“Closing oneself off from the Holy Spirit means not only a lack of freedom; it is a sin,” he said.  

On the other hand, the Pope explained, the world is in need of those who are open to the Spirit.

“The world needs the courage, hope, faith and perseverance of Christ’s followers,” as well as the fruits of the Holy Spirit, as cited in the day’s readings: “love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, self-control” (Gal 5:22).

Pope Francis turned his reflection to the account of the descent of the Holy Spirit on the Apostles and Mary from the day’s first reading.

Receiving this outpouring of the Holy Spirit which filled “their minds and hearts,” the pontiff said, the Apostles “received a new strength so great that they were able to proclaim Christ’s Resurrection in different languages.”

The Pope also how Mary, “the first disciple and the Mother of the nascent Church,” who was present at Pentecost,, “accompanied the joyful young Bride, the Church of Jesus.”

With the coming of the Holy Spirit, the Apostles came to understand all that Jesus had said and done, especially with regard to the “scandal” of his death and resurrection.

“To the Apostles, who could not bear the scandal of their Master’s sufferings, the Spirit would give a new understanding of the truth and beauty of that saving event.”

The Pope explained that the Apostles had hidden themselves away in the Upper Room following Christ’s death out of fear.

“Now they would no longer be ashamed to be Christ’s disciples; they would no longer tremble before the courts of men,” he said.

“Filled with the Holy Spirit,” the Holy Father continued, the Apostles “would now understand ‘all the truth’: that the death of Jesus was not his defeat, but rather the ultimate expression of God’s love, a love that, in the Resurrection, conquers death and exalts Jesus as the Living One, the Lord, the Redeemer of mankind, of history and of the world.”

Pope Francis concluded his homily by reminding the faithful of the responsibilities which come from having received the Holy Spirit.

“The gift of the Holy Spirit has been bestowed upon the Church and upon each one of us, so that we may live lives of genuine faith and active charity, that we may sow the seeds of reconciliation and peace,” he said.   “

Strengthened by the Spirit and his many gifts, may we be able uncompromisingly to battle against sin and corruption, devoting ourselves with patient perseverance to the works of justice and peace.”

Shortly after the conclusion of Mass in the Basilica, Pope Francis led the crowds in Saint Peter’s Square in reciting the Regina Caeli address for the last time for the Easter Season.

In his pre-Regina Caeli address, he recalled the Church’s birth during Pentecost as universal, with a “precise identity” that is nonetheless “open to everyone,” and “which embraces the entire world, without excluding anyone.”

By infusing the disciples with the Holy Spirit, the Pope said, a “new season” of “witness and fraternity” was opened.

“As on that day of Pentecost, the Holy Spirit is continuously poured out on the Church and on each one of us even today, in order that we might leave behind our mediocrity,” and that which keeps us enclosed, “and communicate the Lord’s mercy to the whole world.”