Pope Francis has said priests should emphasise compassion over condemnation when discussing the divisive social issues of abortion, gays and contraception.
Signalling a dramatic shift in Vatican tone, he said the Catholic Church had become obsessed by "small-minded rules" about how to be faithful.
The pope's remarkably blunt message six months into his papacy was sure to reverberate in the US and around the globe as bishops who have focused much of their preaching on such controversial issues are asked to act more as pastors of wounded souls.
In interviews published in Jesuit journals in 16 countries, Francis said he had been "reprimanded" for not pressing church opposition to abortion in his papacy.
But he said in the 12,000-word article that "it is not necessary to talk about these issues all the time".
The pope said: "The church's pastoral ministry cannot be obsessed with the transmission of a disjointed multitude of doctrines to be imposed insistently. We have to find a new balance; otherwise even the moral edifice of the church is likely to fall like a house of cards, losing the freshness and fragrance of the Gospel. The church sometimes has locked itself up in small things, in small-minded rules. The most important thing is the first proclamation: Jesus Christ has saved you. And the ministers of the church must be ministers of mercy above all."
The comments contained no change in church teaching, and the pope said reform should not happen quickly. But it was his clearest declaration yet of a break in tone and style from his immediate predecessors.
John Paul II and Benedict XVI were both intellectuals for whom doctrine was paramount, an orientation that guided the selection of a generation of bishops and cardinals who now face making a dramatic turnabout in how they preach.
Two months ago, Francis caused a sensation during a news conference when he was asked about gay priests. He responded: "Who am I to judge?" about the sexual orientation of priests, as long as they are searching for God and have good will. Pope Francis noted in the latest interview that he had merely repeated Catholic doctrine during that news conference.
But he continued: "A person once asked me, in a provocative manner, if I approved of homosexuality. I replied with another question: 'Tell me: when God looks at a gay person, does he endorse the existence of this person with love, or reject and condemn this person?' We must always consider the person. In life, God accompanies persons, and we must accompany them, starting from their situation. It is necessary to accompany them with mercy. When that happens, the Holy Spirit inspires the priest to say the right thing."