The word honesty means truthfulness, sincerity, or frankness. Another definition is freedom from deceit or fraud. A third definition of honesty is integrity.
Trust is bred by honesty. Those who have a reputation for lying or exaggerating many times can't get someone to believe them on their word alone. A Christian should never be like that. If you are always honest, others will believe you when you simply say yes or no.
Many times people get entangled in their lies. They forget exactly what they have said and in what order it was said. There is a phrase: "Oh, what a tangled web we weave, when first we practice to deceive." How true that statement is!