I'm sure you've seen the movie, "The Diary of Anne Frank," as well as a host of other movies ("Defiance," "The Hiding Place," etc.) where a group of Jewish people are hidden from Nazi soldiers by some hospitable individual or family who is trying to save their lives. Nazi soldiers would come to the house or apartment and search for any Jewish people that may have been there in order to cart them away to their certain torture and death. They would always ask the individual or family whether they were boarding any Jews. The individual and family, of course, would say, No.
I used to ask a question based upon this scenario, because for a long time, I believed that this set up a moral conundrum: If lying is of the devil, as he is the father of all lies, then is it ever right to lie? The answer of whatever person or group I was asking would usually be, No. The second question led me to ask, What if you lived in Nazi Germany and were hiding Jewish people? Would it be morally acceptable to lie? In other words, would the lie, which is always wrong, somehow become right simply because you were trying to save a life? We would usually conclude that it was wrong, but that perhaps because of the intent to save a life, God would have mercy for us not finding a better solution to the problem.
But what is interesting is that, as I taught through the Deuteronomistic History, I began to discover that I had misunderstood a couple of important things. The first one was that lying in the Bible has to do with doing harm to an innocent individual. It does not simply mean "to trick someone." We usually define lying as that which paints a picture to someone that is not true, but this is not what the Bible means by the term. Lying in the Bible is meant to destroy the innocent. That's why the original command is, "Thou shalt not bear false witness against thy neighbor" (Exod 20:16; Deut 5:20). In other words, it is deception perpetrated against one's fellow man in good standing in the community. It has nothing to do with what you say to wicked men. The New Testament citations and references to lying then are qualified by the original command in its Old Testament context.
I began to see, as we worked through Joshua, Judges, Samuel and Kings, that God tells his people to distort reality to either destroy or escape from the wicked. The Israelites are told (by God) to trick the inhabitants of Ai to come out of their walled fortress so that the Israelites can then destroy them (Josh 8:1-7). Jael tells Sisera to come into her tent to be safe and then puts a tent peg through his skull (Jud 5:17-21) and this act is praised, not condemned (6:24-27). God tells Samuel to tell a half truth to Saul as to why he is going to Bethlehem (1 Sam 16:1-5). Michal saves David's life by tricking his messengers with a household idol, and then saves her own life by lying and telling Saul that David threatened to kill her if she did not let him go (1 Sam 19:11-17). David fools the king of Achish into believing that he is insane, since the ancients believed that if you harm someone who is not right in their minds, you will incur the wrath of the gods who protect them (1 Sam 21:10-15). God Himself tells a spirit to go be a lying spirit in the mouths of the prophets of Baal, so that Ahab goes up to war and is killed (1 Kgs 22:19-23). Even in the New Testament, God is said to be the one who sends a deluding influence (lit. "God will send a [supernatural] work so that they believe what is a lie"). All of this seems to be through intermediaries, but the point is that God is the one who tells His people (or spirits) to do this.
I then realized that this is all connected to the meta-ethic of the Scripture that I've discussed many times before: what preserves covenant human life is good, and what works against covenant human life and preservation is evil. I say "covenant" human life in order to make the distinction between the righteous and the wicked, but in reality, as we've discussed before, it is the preservation of true humanity against false humanity that is at stake. Lying is a warfare tactic. It works to preserve the righteous and to end the wicked. It's only when that warfare tactic is turned against the righteous that it becomes evil, as it works against the preservation of true humanity, which is why it is evil.
So telling your wife that she doesn't look pretty in a dress because you don't want to sin is misguided. That has nothing to do with the sin of lying in the Bible. You may want to be honest for other reasons (you don't want her to be embarrassed in public, she really wants to know your opinion to make a decision on what to wear, etc.), but this has nothing to do with the biblical ethic of lying. Lying in the Bible is bearing false witness so that the innocent, true humanity, is not destroyed (of course they are innocent because Christ has made them so, not because they are innocent inherently). My point is simply that when the Nazis come knocking at your door, to not lie is to sin. There is no conundrum. There is no moral dilemma. There is only the preservation of true humanity against false humanity. There is only the ethic of creation and that which flows with creation and that which flows against it, that which works toward a human-filled earth and that which works toward a human-less world (in terms of true humanity, i.e., those who have taken upon the role of the image of God as agents of life). Hence, you should lie your butt off when you need to preserve your or someone else's innocent life from being snuffed out. Tickle the ears of the murderer. But bearing false witness to destroy the innocent or preserve the guilty/wicked is a great evil indeed. Hence, it makes the top ten commandments in the Bible, as lying is a war tactic to preserve the innocent and destroy the guilty.
This is one of many instances where the Bible corrects our misconceptions and religious theories that we impose upon the Scripture from our modern culture. It certainly corrected mine (and frankly there's just something intuitive that we were always misreading that in light of the Nazi scenario). It's not that God would have mercy for our lies to dogs. It's that He would have nothing but praise for us. There is no sin committed. There is only the righteous act of preserving human life, His people, and wiping murderers from the face of the earth. Preserving true human life is the very nature of what is "good" in the Bible. Hence, sometimes lying is a good thing.
So the devil is the father of lies in the biblical sense of the word. He works to deceive true humanity to become and remain false humanity. He is the destroyer, the murderer, of true humanity. He is the one who bears false witness against the truth and against the people of God. But God is the father of preserving human life through all sorts of tactics one would employ in warfare, as He is at war in the world with us. Hence, lying in our modern sense can either mimic the former or the latter, and be evil or good, depending upon to whom and for what purpose the lie is being concocted. I would say as a general rule, always tell the truth, but this post is for those extraordinary circumstances you may find yourself in one day that call for a lie of the divine craftiness variety, and you should know that you have God's full support in such a lie as that.
So the Scripture has corrected me, and I stand corrected. And what I learned was far better than what I thought I knew: that God is the trickster who tricks the tricky. He is the one who catches destroyers of the order that brings life and peace to His people in their own web of deception. He sets His people on a hill to shine with the truth of the gospel in order to preserve the lives of all of His elect. We are to speak the truth of the gospel at all times for this purpose, since we do not know from what guilty men God will make into innocent men. But when it comes to civil issues, no one has the right to withhold a lie if it will save an innocent person's life or lead murderers to their end. After all, we are in this epic battle with God to preserve creation and to destroy chaos. Let us then come to the truth about lying, and be ready to fool Hitler to save a saint, precisely, because that's what God would have us do.