Conservative MP David Davies has launched a scathing attack on the Archbishops of Canterbury and Wales for their calls for Britain to let in more refugees.

The Archbishop of Wales, Dr Barry Morgan, and the Archbishop of Canterbury, Justin Welby, used their New Year and Christmas messages to point out that Jesus was a refugee and to suggest that more refugees should be welcomed to Britain.

But in an article on his website, the MP for Monmouth said: "How wonderfully saintly it must feel to sleep at night with an easy conscience knowing you have roundly condemned the wicked politicians and bigots who worry about mass migration without actually having to take difficult decisions yourself and live with the consequences."

Such views will not fill the pews, Davies warned, citing a recent poll that shows that immigration is the issue of greatest concern to the population, more so than climate change, which is an issue that all church leaders including the Pope refer to frequently.

Davies said: "If Anglican leaders spent a bit more time listening to their rapidly diminishing flocks, they would discover that people want to help genuine refugees but are deeply concerned by the implications of the open door immigration policy which the Church seems to want."

He urged church leaders to heed the huge financial costs of immigraton, not just in terms of providing housing and money to those who come, but in terms of the impact on NHS services, school places and downward pressure on wages, especially for those in low paid jobs.

There are also environmental costs, he added. "The hundreds of thousands who arrive each year and the hundreds of thousands more who the Church want will need houses, roads and workplaces which need to be built in our decreasing number of green areas."

But the most serious costs are cultural, he argued. "Some of those coming to the UK have very different values to our own on issues such as gay rights, women's rights and the right of people to choose to leave their religion and take up another. Much more needs to be done by both Church and state to assimilate people with different values to our own. But the more who come, the harder this will be."

He admitted that church leaders had spoken up about forced marriage and female genital mutilation but challenged them to speak out also on the practice of covering women from head to foot in black. "The burka is now official uniform policy at some UK schools. Surely this is a matter the Church should have a view on," he wrote, quoting the Bible. "The Old Testament makes clear that foreigners living in the land of Israel were expected to obey the laws and customs of the land. It's a message we don't hear much of today."

Davies challenged church leaders to preach a different message.

"The Archbishop willing to confront in person those whose religious values condemn women and gays to being, at best, second class citizens and who would do harm to those converting to Christianity, would be truly walking in the footsteps of He who turned over the tables of the money changers."

A spokeswoman for the Church in Wales said: "We warmly welcome Mr Davies, and anyone else with a limited view of the scope of the ministry and concerns of the Church in Wales and the faith on which it is based, to join us and find out more. Our clergy serve every community in Wales."

The Archbishop of Canterbury's office made no comment.