It is lawful for a Christian to swear an oath falsely (that is, with mental reservation)




According to the roman catholic doctrine on lying, on certain circumstances a man is allowed to swear an oath falsely, that is, with mental reservation. I will explain to you what that means by quoting some words taken from the encyclical Non abbiamo bisogno written by pope Pius XI in 1931 during the Fascist regime in Italy: ‘You ask us, Venerable Brethren, in view of what has taken place, what is to be thought about the formula of the oath, which even little boys and girls are obliged to take, that they will execute orders without discussion from an authority which, as we have seen and experienced, can give orders against all truth and justice and in disregard of the rights of the Church and its souls, which are already by their very nature sacred and inviolable. Takers of this oath must swear to serve with all their strength, even to the shedding of blood, the cause of a revolution which snatches the young from the Church and from Jesus Christ, and which inculcates in its own young people hatred, violence and irreverence without respecting (as recent occurrences have superabundantly proved) even the person of the Pope. When the question is posed in such terms, the answer from the Catholic point of view, as well as from a simply human point of view, is inevitably only one, and We, Venerable Brethren, do not wish to do otherwise than confirm the answer already given. Such an oath, as it stands, is unlawful. Faced as We are by grave anxieties, which We know are also yours, Venerable Brethren, especially those of you who are Bishops in Italy, We are preoccupied first of all by the fact that so many of our children, young boys and girls, are inscribed and have taken membership with that oath. We deeply pity so many consciences tortured by doubts (torments and doubts concerning which We have incontrovertible evidence) precisely because of that oath as it has been interpreted, especially after the recent occurrences. Realizing the many difficulties of the present hour and knowing that membership in the party and the oath are for countless persons a necessary condition of their career, of their daily bread, and even of their life itself, We have sought to find a way which would restore tranquillity to these consciences, reducing to a minimum the external difficulties of the situation. It seems to Us that such a means for those who have already received the membership card would be to make for themselves before God, in their own consciences, a reservation such as "Saving the laws of God and of the Church" or "In accordance with the duties of a good Christian," with the firm proposal to declare also externally such a reservation if the need of it arose. We would desire that Our prayer may move those chiefs of the party who decide its policy and give the orders. It is the prayer of a Father who is jealous for the consciences of so many of his children. Let the reservation just mentioned be included in the oath-formula. Better still, let the oath be dropped, seeing that an oath is an act of religion and that it is out of place on the membership-cards of a political party’ (56-60).

In other words, the pope said to the Italian Roman Catholics: ‘Since you need the membership card of the Fascist party in order to make a career for yourselves and to get your daily bread, and if you do not take the oath prescribed by the Fascist regime you can’t get that card, you are allowed to take the oath prescribed by the Fascist regime, even though that oath is wrong. However, you must take that oath with mental reservation.’ The oath which had to be taken by everybody at that time was as follows: ‘I swear I will execute the orders of the Duce (the Chief, that is, Benito Mussolini) without discussion, and I will defend with all my strength, and if necessary even with my blood, the cause of the fascist revolution.’




To swear an oath with mental reservation is to swear falsely for he who swears an oath with mental reservation swears with the firm intention of breaking his oath for he adds to his oath a mental reservation which – according to him - in due time will enable him to break the oath.

The law says: “Do not swear falsely by my name and so profane the name of your God. I am the Lord” (Leviticus 19:12 – NIV). As you can see, the law condemns those who swear falsely. God will be a swift witness against perjurers (cf. Malachi 3:5).