On Sunday, Pope Francis extended a special greeting to all those around the world who are celebrating Mother's Day, after offering advice on loving to the point of laying down one's life.

"We remember all mothers with gratitude and affection," the Pope said to the crowds gathered in Saint Peter's Square under the hot sun for the recitation of the Regina Caeli prayer May 10.

Speaking to the mothers after granting the apostolic blessing to those present, he noted that the applause from the crowd embraced all mothers: "those who live with us physically, but also those who live with us spiritually."

The Pope also greeted those who were beginning to gather around the Vatican to take part in the March for Life. "It is important to collaborate together in order to defend and promote life," he said.

In his address before the Regina Caeli, Pope Francis recounted Christ's words during the Last Supper: "This is my commandment, that you love one another as I have loved you. Greater love has no man than this, that a man lay down his life for his friends."

Christ says he loves us even though we have not merited this love, the Pope said. "In this way, Jesus shows us the path for following him, the path of love."

Pope Francis explained that Christ's command to love and to lay down one's life for friends is new, insofar as it was he who first fulfilled it.

"The law of love is written once and for all in the heart of man" he said, "written with the fire of the Holy Spirit."

"And with this same Spirit, which Jesus gives us, we too can walk along this path!"

Pope Francis' reflection comes two weeks before Pentecost, on which the Church celebrates the Holy Spirit coming down upon the Apostles 50 days after Christ's resurrection.

The path which leads us out of ourselves toward others is concrete, the Pope said.

"Jesus showed us that love for God puts into effect the love for others," he added, explaining that these two loves go together.

There are many examples of this love throughout the Gospels: "adults and children, educated and ignorant, rich and poor, righteous and sinners, were welcomed in the heart of Christ."

Pope Francis stressed this call to love one another, even when we don't understand each other, or when we don't get along: "It is here that one sees Christian love."

This love is greater than differences of opinion or disposition, the Roman Pontiff said.

A love which has been "freed from selfishness," it gives joy to our hearts.

Pope Francis spoke of the small gestures of closeness shown every day: given to an elderly person, a child, one who is sick, a person alone and in difficulty, without home or job, an immigrant, a refugee.

"The love which Christ has taught us is made manifest in these gestures," he said.