Answer: Some Christians have contended, based upon the above Scriptures, that it is improper for Christians to take oaths, such as when testifying in court, etc. However, Jesus evidently did not forbid our taking an oath before testifying in court, for He Himself answered the high priest after being put under oath by the latter (Matthew 26: 63-66). Jesus prohibited the brethren from taking oaths in their conversation with one another, even as He said, “Let your communication (conversation) be Yea, yea; Nay, nay.”

The appropriateness of this prohibition is twofold: (1) oriental people, including the Jews from ancient times have been accustomed to make an oath to almost every statement they make in private conversation, which naturally tends to belittle the oath, and (2) it should not be done by the Lord’s brethren to one another, because an oath in private conversation implies that the oath-taker’s word of itself without an oath is not to be trusted very much, whereas brethren should trust one another. So viewed Jesus’ statement is a sober principle but has no reference to court’s requiring an oath from witnesses. On the other hand, it is a matter of natural justice for courts to require witnesses to testify under oath, because an oath adds greater solemnity and responsibility to the testimony, since he thereby calls upon God to testify to the truthfulness of his statements and causes him to be more careful “to tell the truth, the whole truth and nothing but the truth.”

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