When the angels informed Avraham that Sarah will give birth, she was listening and heard this prediction. The Torah says she laughed to herself and doubted it could be because, as she put it, VA’ADONI ZAKEN, “…and my husband is old.” (Gen. 18,12) We are then told that Hashem says to Avraham, why did Sarah laugh saying: VA’ANI ZAKANTI, “…and I am old.” (Gen. 12,13) This is not what she had said. She said that Avraham was old.
Our Rabbis point out how serious Lashon Hara is. Here the Torah went to the extent of telling a white lie in order not to cause tension in Avraham’s household.
People are often careless about how they talk. They may have a bit of gossip and before thinking how it may affect someone when this item is recounted to us, they blurt it out. One should think twice before telling tales about others. The Torah even went to the extent to tell a white lie rather than cause strife in Avraham’s home.