Pope Francis leads the opening mass for the synod of bishops on the family at St. Peter's Basilica in the Vatican, Oct. 3, 2015. Reuters

An Egyptian priest doesn't think marriages between Christian women and Muslim men is a good idea, and he wants Roman Catholic leaders to discourage it. During the Synod of Bishops on the family, the priest said that such marriages cause a serious crisis for the married couples and their children, according to the Catholic Herald.

Garas Boulos Garas Bishay, a priest at the Mary Queen of Peace Parish in the Egyptian city of Sharm el-Sheikh, said he is profoundly concerned when Russian and European women marry Muslim men, arguing that the allowance of polygamy in Islam can negatively impact the children they raise. He asked church leaders what they could do to help families with Muslim husbands and Christian wives, in which he argued the wives are sometimes deceived and abused. He also said that the children of these families are often disoriented.

The synod, which began Oct. 4, is a Catholic institution that brings together bishops from across the globe to meet with and advise Pope Francis on questions the church faces, including its stances on gay marriage, divorce and artificial conception. The synod runs through Sunday, and so far its participants have been bitterly fighting much of the time, the Washington Post reported. Traditionalist church leaders have been pushing back against Francis’ attempts to be more inclusive.

At last year’s synod, bishops heard from a Catholic woman from the Ivory Coast who said she and her husband, a Muslim, had lived together for 52 years and have had nothing but respect for each other’s beliefs, according to the Catholic News Service. Members of the synod eventually said that the church has been seeing more marriages between Catholics and non-Catholics, and that the church should help these Catholics practice their own faith while also educating their children as Catholics.