The pope has urged couples to refrain from sexual intercourse before marriage in a new document released by the Vatican.
The document gives couples advice regarding romantic relationships within the Catholic faith.
The "Catechumenal Itineraries for Married Life" guidance says "chastity teaches true love" and defines marriage as "a gift and a task".
"The Church should never lack courage to propose the precious virtue of chastity, even though it is by now in direct contrast with common mentality," the document read.
The 97-pages document also said abstaining from sex while unmarried "deepens" the couple's friendship.
"It is worth helping young spouses to be able to find the time to deepen their friendship and to accept God's grace.
"Premarital chastity certainly favours this course."
For Pope Francis, churches should better prepare couples for marriage to avoid "the suffering caused by broken families".
Writing in the preface, he said churches ought to invest in couples as much as when men seek to become priests or women seek to enter religious life.
He said: "Let us put our minds and hearts at the service of future families."
"I assure you that the Lord will sustain us, give us wisdom and strength, make our enthusiasm grow, and above all, allow us to experience the 'delightful and comforting joy of evangelizing', as we proclaim the Gospel of the family to new generations," he continued.
Reacting to the document, Catholic author Austin Ivereigh told The Telegraph: "This is not a prohibition or a new rule. They are inviting people to follow this path.
"They know it goes against the grain of society. The Church understands that nowadays most people cohabit and have sex before getting married.
"The advice had its merits, since couples who rushed into marriage based largely on sexual attraction might not last very long.
"The idea is for couples to have time to develop all the elements that are crucial for marriage such as patience and communication," he concluded.