The standard of God is that there is no lying, which Exodus 20:16 makes all too clear, “You shall not bear false witness against your neighbor.” However, When Abram was forced to go down to Egypt, because of a famine, he “said to Sarai his wife, ‘I know that you are a woman beautiful in appearance, and when the Egyptians see you, they will say, ‘This is his wife.’ Then they will kill me, but they will let you live. Say you are my sister, that it may go well with me because of you, and that my life may be spared for your sake.’” (12:12-13) In Genesis chapter 20, we find Abraham repeating this behavior, even though it did not bode well for him the first time. Did Abraham lie these two times, and if so, why does the entire account of Abraham present him as righteously walking with God, the epitome of faith?
First, it should be mentioned that Sarah was the half-sister and wife of Abraham. Therefore, in essence, he did not lie about their relationship; he simply withheld information that would have been used by the enemy, resulting in Abraham being possibly killed. It is true malicious lying is prohibited in the Bible, which is to say something that is not true in a conscious effort to deceive or hurt somebody that is deserving of the truth. However, the Bible has examples or cases where a person has withheld information from an enemy, who would have used that information to hurt or cause harm to the person or another. The Bible seems to suggest that we are not under obligation to divulge information to the enemy, as that would cause oneself harm. The American legal system allows something like this as well. It is called The Fifth Amendment (Amendment V), which guarantees you do not have to testify against yourself.
Jesus Christ counseled, “Do not give dogs what is holy, and do not throw your pearls before pigs, lest they trample them underfoot and turn to attack you.” (Matt 7:6) Even Jesus himself, who is incapable of malicious lying, on occasion, withheld information from those who were not worthy of it and would have only used it to hurt him. (Matt. 15:1-6; 21:23-27; John 7:3-10) We see this same principle under way with Abraham, Isaac, Rehab, and Elish, as all pointed in the wrong direction or withheld all the facts from the enemies or non-worshipers.―Genesis 12:10-19; chap 20; 26:1-10; Joshua 2:1-6; James 2:25; 2Ki 6:11-23.