"And behold, it came to pass that Laban was angry, and thrust him out from his presence; and he would not that he should have the records. Wherefore, he said unto him: behold thou art a robber, and I will slay thee."
Laban, having the responsibility of keeping the records, would lose a lot of his position in the eyes of the people if he for some reason or other lost the records. This request being an extreme and very unreasonable in many ways would make anyone in this position angry. But Laban goes beyond the necessary by threatening to kill Laman. Proving Laban's wickedness was pretty far along the scale.
Laban, himself responsibility have hold care for book. Himself loose respect if happen book disappear. Laman ask for book whew, crazy. Laban silly mad. he danger kill Laman. Laban sin bad dirty spirit have.