How to swear an oath at common law

An oath is a religious promise which binds the conscience of the person swearing the oath. At common law, most but not all religions can swear an oath. This page explains the test for whether a particular religion can swear an oath, and the words that should be used.

The test for competence to swear an oath at common law was laid down by the English Court of Chancery in Omichund v Barker 125 Eng Rep 1310 (Ch 1744). There it was held that any person who believed in a god and in the solemn obligation of an oath was competent to testify once they had been sworn in whatever manner their conscience and religious convictions would find binding. The Court also held that:

although the form of oath can vary, the substance is still the same, which is that the person’s god is called upon as a witness to the truth of what is said; and
persons who do not think that their god will either award or punish them in this world or the next, cannot swear oaths because an oath cannot possibly be any tie or obligation upon them.

AD: Need to transfer money or property owed by you to another person? Click here to use this form to easily transfer your property.

Therefore, at common law the minimum requirements for a religion to be able to swear an oath are that the religion has a god (or gods) which the person making the oath believes will punish or reward them in this world or after death. A person who is religious but whose religion does not meet this test is not competent to swear an oath at common law. Statutory modification has altered this position in some jurisdictions, but the common law test is as laid down in Omichund v Barker.

As Omichund v Barker makes clear, it is the substance and not the form of oath which is important. As an overriding rule, a religious person can be asked what form of oath they will regard as binding on their conscience and to swear them accordingly. However some standardised forms of oath have become commonly used. These are set out below.

Words for a Christian oath at common law

At common law, a Christian oath is administered by instructing the deponent to take the Bible in their hand and to say the words:

“I swear by Almighty God that this is my name and handwriting and that the contents of this my affidavit are true.”

The words “and handwriting” can be omitted if the affidavit is entirely typewritten. Variations on the form are also acceptable provided the witness considers their conscience bound by the words and ceremony used. For example, if no Bible is available the witness can still be sworn provided it is their belief that their conscience will be bound by the oath: see eg R v Chapman [1980] Crim LR 42 where the witness failed to take the Testament in his hand.

It is also acceptable for the oath to be administered in a question and answer format, ie:

Q: Do you swear by Almighty God that this is you name and that the contents of this your affidavit are true?

A: Yes / I do / etc.

Words for a Jewish oath at common law

The “standard” form of Jewish oath at common law uses the same words as are used in the Christian oath set out above. The difference is the religious book that is used. There are varying views about whether the book to use should be the Old Testament, the Pentateuch (the first five books of the Old Testament) or no religious book at all. Because the common law does not subscribe any particular form of oath, the witness should simply be asked as to the ceremony they consider will be binding on their conscience. There is no “correct” answer to whether a particular religious book is or is not required: it depends on the person making the oath.

Words for other oaths at common law

The simplest and best practice for other religions is to inquire what oath a witness or deponent will regard as binding and to swear them accordingly. It will often be the case that the witness will regard a form of words which follows those for the Christian oath, but adapted to their beliefs, as sufficient. Hence, provided the witness regards an oath in this form as binding on their conscience, the following formula can be used for any religion which has a god or gods that the deponent believes will reward or punish them in this world or the next:

“I swear by / to [state the deity sworn to by the deponent] that this is my name and handwriting and that the contents of this my affidavit are true.”