One fact remains that will help us in defining a lie.  First, God does not lie (1 Sam 15:29; 1 John 2:21). Second, if God frequently and intentionally withholds the truth or does not tell the whole truth and He does not lie, then, we may better understand it meaning.
For example, 1 Samuel 16 describes Samuel’s plan to go and anoint David as King while Saul was still on the throne. Being afraid for his life, Samuel asks God how he could do this because Saul would hear of it and kill him (1 Sam. 16:2).  The Lord tells him to take a heifer with him and tell Saul that he has come to sacrifice to the Lord. He doesn’t tell him the whole truth and his actions and words are intended to hide Samuel’s true intent to anoint David. Why some cases, withholding the truth and deceiving another is a lie and other times it is not is the issue that we are trying to answer. If the intent of the heart was to deceive, we could make case for that in 1 Samuel 16.  Another element that is used to define lies is the motivation of the lie. Was it done in order to accomplish the will of God and/or accomplish some good for a cause greater than my own personal desires?  Consider, for example, the many good-hearted souls during WWII who hid the Jews from the Nazis and then verbally lied when they were asked if they were housing any of them.  If a lie is a lie and the end never justifies the means, then these people lied to the soldiers who were searching for Jewish families, Rahab lied about the spies, the midwives lied about the Jewish mothers, and Abraham lied about Sarah being his sister.  To argue for the correctness of one’s words despite the intent to deceive as is often heard when one says, “I didn’t say anything that was not true” overlooks the possible intent to deceive. Ananias did not say anything (Acts 5), yet he “lied” to the Holy Spirit and conceived this thing in his heart. When the intent to deceive is motivated by selfish preservation, pride, or selfish ambition, it seems to be an undeniable lie. Some deception, however, is set in Scripture in accomplishing the scheme of redemption and fulfilling the purposes of God. It is a clear deception but the motivation was not precipitated by self-preservation, but for the good of another.  Loving God and our neighbor as ourselves is what should drive all disciples of Christ.  We may be walking out on a slippery slope but there should be no effort to justify one’s actions when the deception was motivated by selfish concerns.
In addition, we may speak falsely out of ignorance. We may have been passing on the report from another source. We may be mistaken about a time when something was done or not remember the sequence of events and the details associated with it and have no intent to deceive. Â
Nor is it a lie if you fail to tell the whole truth — as long as you have no intent to deceive for selfish purposes. The withholding of information may be for the benefit of another or others. It could be deceptive, but not necessarily. “Privacy is a legitimate, necessary [and Biblical] part of life. People do not have the right to know everything. We are required not to lie; we are not required to tell all we know”(Ephesians Snodgrass). Sometimes withholding truth can be deceitful, but that would have to be determined on a case-by-case basis.