The European Union was inspired by "gospel values", Catholic bishops in Northern Ireland told the faithful, as they warned of the consequences of Brexit.
The bishops urged Christians to "take seriously our responsibility as citizens to inform ourselves and to vote on the issue at stake". Although the statement released on Wednesday said the decision of how to vote in this month's referendum was "clearly" one "for individuals", the Church leaders went on to say that the "vision and values inspiring the European project are also gospel values".
The bishops praised the EU extensively and warned of the "profound implications" if Britain voted to leave.
"The reintroduction of border controls, for example, would not only have profound implications for trade and the economy, but also for the wider civil society, notably through the disruptive impact on the day-to-day life of those who live in border areas or cross the border frequently," said the bishops.
"The valuable work carried out to date to build new relationships across these islands must not be undermined."
The statement was released on the second day of the Irish bishops' summer meeting, but only on behalf of bishops north of the border as it is only Northern Ireland that will vote in the June 23 referendum.
They hailed the "remarkable achievement" of the EU in preventing war and bringing about the "peaceful and effective integration and co-existence between peoples of differing histories, culture and backgrounds".
The statement quoted from Pope Francis' address to the European Parliament as an indication of Catholic attitudes towards the EU.
"At the heart of this ambitious political project was confidence in man, not so much as a citizen or an economic agent, but in man, in men and women as persons endowed with transcendent dignity," Francis said in his November 2014 speech.
The bishops added: "In an ever more interdependent world, the EU provides individual member states with a valuable mechanism of international influence in terms of peace-making, development, trade negotiation and shared environmental responsibility, in support of the global common good."