Chp. 32 verses 25 - 33: Yaakov wrestles with Esau's angel and is victorious. However, the angel is able to injure him in his thigh. He will not allow the angel to leave until his receives a blessing. G-d makes the sun rise early so that Yaakov can be healed from his injury. To commemorate this event Hashem commands us not to eat the "gid ha nashaw" the sciatic nerve.