Recognizing and encouraging the importance of strong and unified families is especially needed today when "the family is subjected to misunderstanding and difficulties of various kinds, which weaken it," he said Dec. 27 before praying the Angelus with visitors gathered in St. Peter's Square.
Marking the Jubilee of Families during the Holy Year of Mercy, the Pope dedicated a morning Mass and his noon Angelus address to the example and witness of the Holy Family of Jesus, Mary and Joseph.
The day's Gospel reading "invites families to welcome the light of hope originating from the house of Nazareth," he said in remarks before the Angelus.
The Holy Family demonstrates what God desires for all families -- that they be "a special community of life and love," he said.
Mary and Joseph teach men and women today to welcome children as a gift of God, to raise them in a way that cooperates with God's divine plan, and to give "the world, with every child, a new smile."
"The true joy that's experienced in the family isn't something random or accidental. It is a joy that is the result of the deep harmony between people, who savor the beauty of being together, of supporting each other on life's journey," he said.
That joy also is always rooted in "God's presence, his welcoming love, mercy and patience toward everyone. If one doesn't open the door of the family to God's presence and his love, the family loses harmony, individualism prevails and joy is extinguished," he said.
The Pope prayed that the Holy Family protect the world's families so that they may live in "serenity and joy, justice and peace."
Earlier in the day, the Pope celebrated a special Mass in St. Peter's Basilica dedicated to families.
In his homily, he said the Holy Family show the importance of prayer, sacred Scripture, worship and praising God together as a family.
The Pope suggested mothers and fathers bless their children at the start and end of each day, by making the sign of the cross on their children's foreheads like they did at their baptism. "Bless them, that is, entrust them to the Lord," he said, "so that he can be their protection and support throughout the day."
It's also important families pray before meals, thanking God "for these gifts and to learn how to share what we have received with those in greater need."
Family life is a shared journey of ups and downs, and mistakes can become occasions for forgiveness and growth, the Pope said.
"In the Year of Mercy, every Christian family can become a privileged place on this pilgrimage for experiencing the joy of forgiveness," he said.
"Forgiveness is the essence of the love which can understand the mistakes and mend them," he said. In fact, "how miserable we would be if God did not forgive us."
That is why people learn how to forgive starting in the family, he said, because it is in the family that people can be sure they are understood and supported no matter what mistakes are made.
"Let us not lose confidence in the family," he said, since it is "beautiful when we can always open our hearts to one another, and hide nothing. Where there is love, there is also understanding and forgiveness."
Pope Francis also focused on the importance of forgiveness the previous day, Dec. 26, the feast of St. Stephen, who is remembered as the first Christian martyr.
Like Christ forgave those who crucified him, Stephen forgave those who stoned him to death, the Pope said before reciting the Angelus.
A true witness of Christ is someone who acts just like Jesus -- someone "who prays, loves, gives, but above all who forgives, which, just like the word says, is the highest expression of giving."
"If we want to grow in the faith, first and foremost, it's necessary to receive God's forgiveness; to encounter the father, who is ready to forgive everything and always."
"We must never tire of asking for divine forgiveness because only when we are forgiven, when we feel forgiven, we learn to forgive."
It's not easy to imitate Christ and forgive the small or significant wrongs and injustices experienced in life, the Pope said. But like Christ and St. Stephen, it can be done starting with prayer and entrusting the person who has done wrong to God's mercy, he said.
"One then discovers that this internal struggle to forgive is cleansed of evil and that prayer and love free us from the internal chains of rancor."
The Pope said, "It is so terrible to live with rancor" so people should use every day as an opportunity to "practice forgiveness." That way people will become more merciful and "we will overcome evil with good, transforming hatred into love" and making the world more pure.
The Pope also asked people pray for all those being persecuted for their faith -- "our many martyrs of today" who are "unfortunately very many."