One of Ireland's most senior Catholic clerics has called for the Church to take a "reality check" following the country's overwhelming vote in favour of same-sex marriage.
The first gay marriages are now likely to take place in the early autumn.
Diarmuid Martin, the archbishop of Dublin, said the Church in Ireland needed to reconnect with young people.
The referendum found 62% were in favour of changing the constitution to allow gay and lesbian couples to marry.
The archbishop told the Irish broadcaster RTÉ: "We [the Church] have to stop and have a reality check, not move into denial of the realities.
"We won't begin again with a sense of renewal, with a sense of denial.
"I appreciate how gay and lesbian men and women feel on this day. That they feel this is something that is enriching the way they live. I think it is a social revolution."
The archbishop personally voted "No" arguing that gay rights should be respected "without changing the definition of marriage".
"I ask myself, most of these young people who voted yes are products of our Catholic school system for 12 years. I'm saying there's a big challenge there to see how we get across the message of the Church," he added.
Ireland is the first country in the world to legalise same-sex marriage through a popular vote, and its referendum was held 22 years after homosexual acts were decriminalised in the Republic of Ireland.
Among those voicing their approval of the outcome was UK Prime Minister David Cameron who tweeted: "Congratulations to the people of Ireland, after voting for same-sex marriage, making clear you are equal if you are straight or gay."
Feargha Ní Bhroin and Linda Cullen were among those who were pleased at the result of the referendum.
Ms Cullen proposed to her partner live on BBC Radio 5 Live on Sunday.
The couple, who have been together 10 years, said marriage was especially important for them as they have children.
"It means a lot in this country to be married and to have that status for your family," Ms Cullen said.
By BBC's Ireland correspondent Chris Buckler
In Ireland debates about morality tend to be rooted in religion. The discussion about same sex marriage was no exception.
The Catholic Church after all still has much influence in Ireland and the no vote was strongest in rural areas where church attendance figures tend to be higher. That sharply compared to the cities where the yes campaign never doubted their support.
There was also a generational divide - with the yes campaign capturing the interest and enthusiasm of young people in a way that few elections do. Some living abroad even returned home to Ireland simply to visit the ballot box.
The Catholic Church is not immune from the influence of an increasingly liberal Ireland.
In his appeal for a no vote the church's most senior figure In Ireland specifically recognised the love shared between same sex couples.
That is a softening of language and in its own way a sign of wider change.
In total, 1,201,607 people voted in favour of same-sex marriage, while 734,300 voted against.
Out of 43 constituencies, only the largely rural Roscommon-South Leitrim had a majority of "no" votes.
The yes vote means an amendment will be made to Article 41 of the constitution, stating that being of the same sex is no longer an impediment to marriage.
The government must bring in a new law, the Marriage Bill 2015, to give effect to the amendment and it says it hopes to do that by the time the Irish parliament breaks up in the summer.
This means the first actual marriages are unlikely to take place until September.
Same-sex marriage is now legal in 20 countries worldwide.
What the 'yes' vote means
The Republic of Ireland has a written constitution which can only be changed by referendum.
Now that the proposal has been passed, a marriage between two people of the same sex will have the same status under the Irish constitution as a marriage between a man and a woman.
They will be recognised as a family and be entitled to the constitutional protection for families.
Civil partnerships for same-sex couples have been legal in Ireland since 2010, giving couples legal protection which could be changed by the government.
However, married gay people will now have a constitutional standing that can only be removed by another popular vote.
According to the Irish Times, there will be no new civil partnerships from the day the law comes into effect, and although civil partners will retain their existing rights, there will be no automatic upgrade from partnership to marriage.