A reader has asked for some commentary on the subject of the commandment against false witness (Ex. 20:16/Dt. 5:20) and how this fits in with such things as the "honorable lie" as an action. In modern times this would also include such things as the repeatedly-used "hiding Jews in the cellar when Nazis come by" situation, as well as things like a spy in a foreign country.
There are a couple of points we can make here. The first and most obvious is that ancient law codes were didactic rather than absolute. This means that although this commandment is expressed in absolute terms, this does not necessarily mean it will not brook exceptions. Some of the "Big Ten" would be hard to get any leeway out of (like not serving other deities), but we can say with certainty that the Sabbath command did, even by Jesus' own assertion.
But of more relevance, even if more obscure, is the specific phrasing of the commandment: Do not bear false witness. The specific words used relate to the bearing of legal witness in court. Examples confirm this – not all uses of “false witness” have defining contexts, but the ones that does indicates a legal setting:
Deut. 19:16-18 If a false witness rise up against any man to testify against him [that which is] wrong; Then both the men, between whom the controversy [is], shall stand before the LORD, before the priests and the judges, which shall be in those days; And the judges shall make diligent inquisition: and, behold, [if] the witness [be] a false witness, [and] hath testified falsely against his brother…
In addition, uses of the word “witness” reflect a legal context:
Gen. 31:44 Now therefore come thou, let us make a covenant, I and thou; and let it be for a witness between me and thee. (One of many passages where the word is used in the context of covenant agreements.)
Lev. 5:1 And if a soul sin, and hear the voice of swearing, and [is] a witness, whether he hath seen or known [of it]; if he do not utter [it], then he shall bear his iniquity.
Num. 35:30 Whoso killeth any person, the murderer shall be put to death by the mouth of witnesses: but one witness shall not testify against any person [to cause him] to die.
Ruth 4:10-1 Moreover Ruth the Moabitess, the wife of Mahlon, have I purchased to be my wife, to raise up the name of the dead upon his inheritance, that the name of the dead be not cut off from among his brethren, and from the gate of his place: ye [are] witnesses this day. And all the people that [were] in the gate, and the elders, said, [We are] witnesses. The LORD make the woman that is come into thine house like Rachel and like Leah, which two did build the house of Israel: and do thou worthily in Ephratah, and be famous in Bethlehem…
Ps. 35:11 False witnesses did rise up; they laid to my charge [things] that I knew not.
Jer. 32:10 And I subscribed the evidence, and sealed [it], and took witnesses, and weighed [him] the money in the balances.
The commandment is thus narrower in its application than is commonly believed.
Of course, this is not to say that dishonesty on matters outside court gets a free ride! But as is usually the case, our applications of these texts is not the black and white matter so many critics (and even some believers) suppose it to be.