Introduction Jealousy can be defined as the emotional feeling that entails anger, insecurity, fear coupled with anxiety over the expected loss of a valuable to someone else. Unlike envy, jealousy is felt over a valuable thing that one is in possession of and does not want to let go. Envy on the contrary is felt over valuables that one is not in possession of and wishes to have or wants to stop others from acquiring them. Both jealousy and envy amount into rivalry which is a battle or motivated strive also defined as the competition to win over a valuable. Sibling rivalry is thus a type of rivalry that is felt in the form of competition within a family and is restricted to brothers or sisters whether of the same blood or not. In the biblical context jealousy runs in many family set ups in the Old Testament and it has been described as a sin whose consequences may run from one generation to the next. The Old Testament with regard to the first two books of the law, Genesis and Exodus illustrates jealousy and sibling rivalry among various biblical families.All the cases implicated amount into a different sin that calls for God’s punishment or approval.God himself has been implicated in jealousy and the bible cites with reference to some of the cases of jealousy that God approved or did not send punishment. The case of Cain and Abel The Old Testament records the first case of sibling rivalry between Cain and his brother Abel (Gen 4, 4-9).Cain as the bible records was jealousy of the acceptance of his brother’s offering before God and disobeyed God’s warning by taking his brother’s life.Gen 4, 7 emphasizes that the sin committed by Cain was punishable and is very common among the human race that is been covered in the impunity of sins committed by their fore generations. The consequence of the sin implicated in Abel’s murder is a judgment that is bound to follow generations (Genesis 4) The Case of Jacob and Esau Gen 25 records the second form of sibling rivalry in the Old Testament between Esau and his brother Jacob. The two were sons of Isaac and Rebekah and the grand children of Abraham and Sarah. Esau who happened to be older than Jacob had been promised the last and only blessing from his father Isaac.Rebekah on hearing of the husband’s intention disclosed the secret to the younger brother Jacob and helped him get the blessing before Esau’s arrival. The bible however documents that Rebekah was aware that the lord himself had earlier indicated his liking that the young brother be served by his eldest brother and may be did what she did in accordance to God’s plan.Isaac may have been aware of the plan as well but was not pleased with his young son’s conduct. The rivalry implicated in this case was geared by parental preference for either of the sons. Esau was Isaac’s best owing to his outstanding hunting that assured him of some game supply while the young brother who happened to be the mother’s best was an idler that preferred staying at home. Esau wished to have Jacob pay back dearly for taking away what was initially meant for him and Jacob had to seek refuge by fleeing from him. God indeed did not punish Jacob for his deception but instead saved him from his brother’s anger.This could have been because he was pleased that Jacob serves him irrespective of his conduct and father’s dislike. God may have wanted to have other genera