Genesis 37:4
And when his brethren saw that their father loved him more than all his brethren, they hated him, and could not speak peaceably unto him. And when his brethren saw that their father loved him more than all his brethren, they hated him, and could not speak peaceably unto him.
Jacob loved Joseph more than all his other sons because Joseph was pure and excellent in character, cheerful and happy and full of love for his father, so that his father's heart was bound up in him, while his other sons pursued a wicked course that grieved their father, brought him shame, and made his life bitter. Jacob expressed this preference openly and unwisely, manifesting a partiality that was wrong. The brothers believed Joseph had taken their father's affection from them and felt unfairly deprived of his confidence and love.
Their awareness that their father loved Joseph more stirred envy that grew and deepened into hatred, destroying their ability to speak peaceably to him. That hatred was further angered by Joseph's faithful obedience and by his remonstrating with them over their wicked course and daring to reprove those much older than himself, for which they accused him of spying on their actions. When his entreaties only excited wrath he laid their evil plans and purposes before his father, giving Jacob knowledge he otherwise would not have had, and their resentment grew at this exposure of their wrongdoing.
They hated him because he was innocent, righteous, and beloved of his father while they were wicked and a source of grief to him. They recognized and even admired his purity and goodness but would not leave their wicked course to become virtuous and noble like him, overlooking that their own conduct caused their father's estrangement and brought shame upon him. Their hatred called out a revengeful disposition and was concealed under apparent repentance while they hid their bitterness. It grew into murderous hatred and was the same spirit that moved Cain against his brother.
Jacob's partiality angered the brothers and helped provoke their cruel treatment of Joseph, while it also encouraged faults in Joseph, including self-sufficiency and being exacting. Their envy led them to sell Joseph in hope of keeping him from becoming greater than they were, but God overruled their plan so that Joseph's dreams would be fulfilled. For God had chosen Joseph while young to do a special work for His people.