The long read: why Catholics shouldn’t marry non-Catholics

We find ourselves approaching the end of the summer Wedding Season, and whilst many Catholics will find themselves newly-married or engaged, others will be discerning their vocation to marriage more keenly. This raises a question that is significant for the future of individual Catholics and the life of the Church herself: ‘What sort of person ought we to court, and marry?’ For many, the answer seems obvious: “Whomever we fancy”. That is not the Church’s answer however, and it never has been.

Until the late 20th century, Catholic teaching on prospective spouses was well-known: Catholics should marry Catholics, and any union with those outside the Church – a ‘mixed’ or ‘exogamous’ marriage – is gravely contrary to the faith. To marry only another Catholic was even listed as a ‘precept’ of the Faith, as firm an injunction as attending Holy Mass on Sundays.

The Catholic Encyclopaedia puts it starkly: “From the very beginning of its existence the Church of Christ has been opposed to such unions. As Christ raised wedlock to the dignity of a Sacrament, a marriage between a Catholic and a non-Catholic was rightly looked upon as degrading the holy character of matrimony, involving as it did a communion in sacred things with those outside the fold”.

Yes, shocking as it may seem today, the Church really has traditionally taught that you should not marry a non-Catholic for one of the same reasons that you should not share Holy Communion with them: doing so debases a Sacrament, falsely expressing a full communion where such does not and can not exist. The pastoral reality of frequent Catholic inter-marriage with Lutherans in Germany has led to recent attempts by the German Bishops to abrogate the Church’s historic proscription of inter-communion, precisely for the sake of Protestant spouses. The very opposite approach would be more consistent with the Church’s teaching: to discourage mixed marriages because of what shared communion in the Body and Blood of the Lord means.

If you find that strident, Denzinger’s ‘Enchiridion Symbolorum’, the closest thing we have to a comprehensive source book for Catholic doctrine, illustrates Catholic teaching on mixed marriages with three particularly prohibitive Papal pronouncements. The earliest statement is from Pope Hadrian I (772-795), who in a letter on errors in the Spanish Church, mentions matter-of-factly that “it is not permitted for anyone to marry an infidel”. Likewise, Pope Pius VI (1775-1799) sent a letter to the cardinal and bishops of Belgium in 1782, in which he insists that “we must not depart from the uniform opinion of our predecessors and from ecclesiastical discipline, which do not approve marriages… between a Catholic on the one hand, and a heretic on the other”.

Four decades earlier, Pope Benedict XIV (1740-1758), in a declaration on marriage in 1741, grieved that there were Catholics “who, becoming shamefully deranged by a mad love, do not wholeheartedly abhor and think that they should refrain from these detestable marriages which Holy Mother Church has continually condemned and interdicted”, praising zealous bishops who “endeavour to restrain Catholics from uniting themselves to heretics in this sacrilegious bond”. He goes on to exhort all clergy to “deter, as far as they can, Catholics of both sexes from entering into marriages of this kind to the destruction of their own souls”.

These last two 18th-century Popes were both setting out rules on marriages in the Low Countries, where Catholics and Protestants often lived cheek-by-jowl. Both only made allowances for their occurring under strictly penitential conditions. Benedict XIV exhorted that “the Catholic spouse… in proportion to the very grave fault he has committed… should do penance and ask pardon from God, and should try… to draw the other spouse, who is straying from the true faith, back to the bosom of the Catholic Church, and to win her or his soul, which indeed would be a very excellent means of obtaining pardon for the crime committed”.

Pius VI similarly allowed a Catholic who had entered into a mixed marriage to return to the Sacraments “as long as he shall demonstrate that he is sorry for his sinful union… sincerely declare before confession that he will procure the conversion of his heretical spouse… renew his promise of educating his children in the orthodox religion, and that he will repair the scandal he has given to the other faithful”. He also forbade any priest from assisting at the wedding “in a sacred place, nor clothed in any vestment betokening a sacred function, nor will he recite over the contracting parties any prayers of the Church, and in no way shall he bless them”.

“Harsh stuff!” you might think, surely redolent of an unkindly triumphalistic and grossly sectarian past. On the contrary however, though it goes scandalously uncommunicated from the pulpit or during ordinary pastoral care, opposition to mixed marriages is still the Church’s magisterial position. Moreover, so far from being generated from bigoted prejudice, it flows from the consistent teaching of Holy Scripture and Sacred Tradition.

St Paul addresses the issue directly: “Do not be mismated with unbelievers. For what partnership have righteousness and iniquity? Or what fellowship has light with darkness? What accord has Christ with Be’lial? Or what has a believer in common with an unbeliever?” (2 Corinthians 6:14). This clear proscription continues the teaching of the Old Testament, in which the Israelites are banned from inter-marriage with foreign nations (e.g. Malachi 2:11; Ezra 10:10-11; Nehemiah 10:31; Deuteronomy 7:3-4) partly due to the threat of their faith being mixed with false religion and compromised by idolatry (e.g. Numbers 25:1-9; cf. 1 Corinthians 10:8).

If this seems narrow or restrictive, it shouldn’t do. It makes complete sense when we realise the meaning of matrimony according to Christian teaching, and how marital relationships are meant to work. The primary and secondary purposes of marriage – to generate and nurture children, and the mutual help of the spouses – could be summarised together as one purpose: to form a Christian family. Or, in the words of Vatican II (Lumen Gentium 11), an ecclesia domestica, or ‘domestic church’.

The Catechism recalls the Council’s use of this ancient phrase, and states the mission of familial life (CCC, 1655-1657): “In our own time, in a world often alien and even hostile to faith, believing families are of primary importance as centres of living, radiant faith”. In this context, the family can be “the first school of Christian life” in which parents can be “by word and example… the first heralds of the faith with regard to their children”, fostering their vocations. The implication here is critical: devoutly practising Catholic families are more important than ever.

For spouses too, it is in the ‘domestic church’ that a Catholic marriage can best fulfil St Paul’s admonitions in Ephesians 5, in which the simile of a husband’s love for his wife is “as Christ loved the Church and gave Himself up for her, that He might sanctify her”, and in which marriage is seen as a “great mystery” symbolising Christ and the Church (Ephesians 5:25-26, 31-32; cf. Genesis 2:24).

The Church’s historic opposition to mixed marriages then, is not based on antipathy towards non-Catholics, but a faithful apostolic care for Christian matrimony and the family. We also realise why it is also still officially reflected in the Catechism (see sections 1633-1637) and Canon Law, even if this is framed in rather gentler terms than in past generations. The wisdom of this teaching is especially discernible once we see that the everyday general reality of the alternative is sadly a demonstrable failure.

For practising Catholics, our relationship with God should be the most essential element of our lives. If however, we marry an atheist or agnostic, a follower of a non-Christian religion, a non-Catholic Christian, or a heterodox (‘dissenting’) or ‘lapsed’ Catholic, we are binding ourselves to a person with whom marriage is either not a Sacrament, or not properly able to function as a means of God’s grace to us. We are also joining our lives to someone for whom fully orthodox Christianity is something towards which they can be at best indifferent, and at worst averse.

Many Catholics in mixed marriages can sadly recall the pain of going to Holy Mass or Communion alone, of not being able to pray or discuss their faith with their husband or wife, or not being completely understood by the pre-eminent person in their life. The non-Catholic does not have to be hostile to undermine their spouse’s spirituality. Often they may simply and quite understandably not want to do ‘Church things’, leading the Catholic to forego attending devotional events or engaging in their religion more, so as to avoid annoying or upsetting their significant other and spend more time with them. Though the non-Catholic may not intend it, this distracts from and impedes their loved one’s faith.

These realities occur in best case scenarios, but become much worse if the non-Catholic becomes actively antagonistic, even in subtle ways. The number of Catholics who have fallen away from the faith out of exhaustion with the challenging, occasional mockery, and non-cooperation of their unbelieving spouse, especially on difficult subjects like contraception, is depressing to contemplate.

This ‘mismating’ as St Paul calls it, even whilst dating, can be hugely detrimental to our spiritual lives. When an atheist boyfriend guilts a Catholic girlfriend into sleeping with him, or an apathetically secular girlfriend draws her Catholic boyfriend into bad company or even just into spending time with her at the expense of attending the Sacraments, it is clear such relationships lead Catholics to fall into grave harmful sin, or even risk lapsing altogether. The concerns underlying St Paul and the Old Testament writers, are as relevant today as they have ever been.

Even if mixed marriages did not damage the faith of Catholics, they are more often likely to fail. Data compiled by Georgetown University’s Centre for Applied Research in 2013 found that American Catholics who married Protestants had a divorce rate of 49 per cent. For those with non-religious spouses this was 48 per cent, and with religious non-Christian spouses, 35 per cent. By contrast, US Catholics who married Catholics had a 27 per cent divorce rate.

If mixed marriages cannot perfectly fulfil the second purpose of marriage – the unity of spouses – even in the best of circumstances, they can also fail to fulfil the first: the procreation and right rearing of devout children. A study by the U.S. Pew Research Centre in 2016 found that 62 per cent percent of children in families in which both parents were Catholic, remained Catholic as adults. In families where one of the parents had no faith this number plummeted to 32 per cent (42 per cent becoming non-religious and 20 per cent becoming Protestant), whereas where one parent was Protestant only 29 per cent remained Catholic (with 38 per cent becoming Protestant, and 26 per cent becoming non-religious). In other words, mixed marriages around halved the chances that children of Catholics would retain the faith.

The indifference alone of the non-Catholic spouse can act as an ‘anti-witness’ to their offspring. This is particularly true of fathers. When children see that Dad does not go to Church, the implication is that it might not after all be that relevant, but just an eccentric personal hobby of Mum. The same can be true when the mother does not attend, but fathers evidently have a particular influence.

A Swiss study in the 90s found that of families in which both parents attended Sunday services consistently, 74 per cent of the children went on to attend regularly or sporadically. When fathers alone took their children, this declined to 62 per cent. Illustrating the spiritual importance of Dads, when the mother alone took the children to church the figure plummeted to 39 per cent. Given that the preponderance of mixed marriages involve Catholic women, this is a profound problem, and part of the reason for the phenomenon of mass lapsation.

As goes the family so goes the Church, and one reason for the decline in faithful Catholics is due to the lack of complete Catholic homes, because of the increased preponderance of mixed marriages.

Even were this not so, when one parent is not a practising Catholic, the children lose that ‘school of faith’ that the Church expects a ‘domestic church’ will form. Those of us who went without a father who could lead us in family prayer, a mother who could explain the faith to us, or either who could be masculine and feminine Christian role models of orthodox faith and charity – as well as examples of what to look for in future spouses – experience this lack most keenly.

In defence of mixed marriages, some will point to a person they know who became a Catholic after years of being married to one, perhaps through the witness of their spouse and their Catholic children. Such stories are wonderful, but putting aside how often they actually occur, the moral taken from them is not a sound one.

If you marry someone, you do so because you love them as they are, not as the person you want them to be or aim to help them become. Being in a relationship with someone you hope to change is widely and rightly regarded as foolish, and most likely doomed to failure. To try to use a romantic attachment as a means of conversion is a dishonest enterprise, and may even ultimately push the object of your efforts further away from Christ if they end up associating the Faith with a messy break-up. In short, if you want to evangelise another you should do it outside, not inside, courtship.

In the light of all this, the idea that the Church’s teaching is ‘close-minded’ seems bizarre. We generally agree that when two people marry, they should concur on their most valued principles and life activities. If someone were to feel that playing or listening to music of some form is essential to their daily happiness, would they look for and let themselves fall in love with someone who was utterly indifferent to that music, or even hated it? Of course not. Why then would a Catholic look and allow themselves to fall for someone with whom they cannot – at least fully and integrally – share the paramount part of their life?

Catholics should not marry non-Catholics, and for that reason, Catholics should not court non-Catholics. To do so is an act of gravely reckless imprudence. Such a choice contradicts the plain and perennial teaching of Holy Scripture, Sacred Tradition, and the Church’s Magisterium, if only on what a marriage ought to be. Not only that, but in so clearly compromising the Catholic family, it undermines the life of the Church herself.

When a successful marriage is hard enough to achieve without the profound problems that mixed marriages provoke, pastors need to faithfully expound the Church’s long-neglected but crucial teaching on this issue to their parishioners. Just as importantly, those of us who are unmarried Catholics need to ask ourselves how we may fully flourish as future spouses, and how the marriages we aspire to may truly form the symbols that they are meant to be of the relationship between Christ and His Church. The answer is that they can only authentically become so when we marry someone who shares the same faith, and has the same access to God’s Grace, in His one, holy, Catholic and Apostolic Church.