Jacob erred by showing strong favoritism to Joseph:

Genesis 37:1. And Jacob settled in the land of his father’s sojourning, in the land of Canaan. 2. These are the descendants of Jacob. Joseph, seventeen years old, was tending the flock with his brothers and he was a lad with the sons of Bilhah and with the sons of Zilpah, his father’s wives. Joseph brought to their father very evil reports about them. 3. Now Israel loved Joseph more than all his children, because he was the son of his old age and he made him a long tunic. 4. And when his brothers saw that their father loved him more than all his brothers, they hated him and could not speak peaceably to him.