"There are at least two instances in the Bible where lying produced a favorable result. For example, the lie the Hebrew midwives tell Pharaoh seems to result in the Lord’s blessing on them (Exodus 1:15-21), and it probably saved the lives of many Hebrew babies. Another example is Rahab’s lie to protect the Israelite spies in Joshua 2:5. It is important to note, however, that God never condones these lies. Despite the “positive” outcome of these lies, the Bible nowhere praises the lies themselves. The Bible nowhere states that there are instances where lying is the right thing to do. At the same time, the Bible does not declare that there is no possible instance in which lying is an acceptable option.

The question then remains – is there ever a time when lying is the right thing to do? The most common illustration of this dilemma comes from the life of Corrie ten Boom in Nazi Germany. Essentially the story is this: Corrie ten Boom is hiding Jews in her home to protect them from the Nazis. Nazi soldiers come to her home and ask her if she knows where any Jews are hiding. What is she to do? Should she tell the truth and allow the Nazis to capture the Jews she was trying to protect? Or, should she lie and deny that she knows anything about them?

In an instance such as this, where lying may be the only possible way to prevent a horrible evil, perhaps lying would be an acceptable thing to do. Such an instance would be somewhat similar to the lies of the Hebrew midwives and Rahab. In an evil world, and in a desperate situation, it may be the right thing to do to commit a lesser evil, lying, in order to prevent a much greater evil. However, it must be noted that such instances are extremely rare. It is highly likely that the vast majority of people in human history have never faced a situation in which lying was the right thing to do." Full text: Is it ever right to lie? http://www.gotquestions.org/right-to-lie.html

Lying: (Heb. šeqer, ‘falsehood’, ‘deception’; kāzāḇ, ‘lie’ or ‘deceptive thing’; Gk. pseudos and cognates). Essentially, a lie is a statement of what is known to be false with intent to deceive (Jdg. 16:10, 13). Biblical writers severely condemn aggravated forms of lying, e.g. those which perpetrate a fraud (Lv. 6:2–3) or secure wrongful condemnation (Dt. 19:15), and the testimony of false prophets (Je. 14:14). Lies may be expressed in words (Pr. 6:19), a way of life (Ps. 62:9), error (2 Thes. 2:11), or a false form of religion (Rom. 1:25). The prophets regarded lying as a specific expression of the principle of evil (Ho. 12:1). Lying is prohibited as repugnant to the moral conscience of Israel (Pr. 19:22), because of its antisocial effects (Pr. 26:28), and, above all, as incompatible with the divine nature (Nu. 23:19). Jesus declares that Satan is the father of lies (Jn. 8:44). All falsehood is forbidden in the Christian community (Col. 3:9).

Lying is characterized in various ways, e.g. Cain’s evasive answer (Gn. 4:9), Jacob’s deliberate falsehood (Gn. 27:19), Gehazi’s misrepresentation of his master (2 Ki. 5:21–27), and the deception practised by Ananias and Sapphira (Acts 5:1–10). Lying is the sin of Antichrist (1 Jn. 2:22) and all habitual liars forfeit eternal salvation (Rev. 21:27).

1 Sa. 16:2 does not justify the expedient lie. God merely suggested an ostensible reason for Samuel’s visit to Bethlehem, and the prophet was under no obligation to divulge his real purpose. Again, 1 Ki. 22:20–23 implies that God permitted a subterfuge that his righteous judgment should be enacted upon Ahab. In such passages as Gn. 12:10–20 it is clear that deception is not condoned nor recorded as an example to follow.