Gen 25:26 | KD | STEP | When she was delivered, there were twins; the first-born was reddish, i.e., of a reddish-brown colour ( ; ), and “all over like a hairy cloak,” i.e., his whole body as if covered with a fur, with an unusual quantity of hair ( hypertrichosis ), which is sometimes the case with new-born infants, but was a sign in this instance of excessive sensual vigour and wildness. The second had laid hold of the heel of the first, i.e., he came into the world with his hand projected and holding the heel of the first-born, a sign of his future attitude towards his brother. From these accidental circumstances the children received their names. The elder they called Esau, the hairy one; the younger Jacob , heel-holder: יעקב from עקב ( denom . of עקב heel, Hos 12:3), to hold the heel, then to outwit ( ), just as in wrestling an attempt may be made to throw the opponent by grasping the heel.

‏ Genesis 25:26

When she was delivered, there were twins; the first-born was reddish, i.e., of a reddish-brown colour (1Sa 16:12; 1Sa 17:42), and “all over like a hairy cloak,” i.e., his whole body as if covered with a fur, with an unusual quantity of hair (hypertrichosis), which is sometimes the case with new-born infants, but was a sign in this instance of excessive sensual vigour and wildness. The second had laid hold of the heel of the first, i.e., he came into the world with his hand projected and holding the heel of the first-born, a sign of his future attitude towards his brother. From these accidental circumstances the children received their names. The elder they called Esau, the hairy one; the younger Jacob, heel-holder: יעקב from עקב (denom. of עקב heel, Hos 12:3), to hold the heel, then to outwit (Gen 27:36), just as in wrestling an attempt may be made to throw the opponent by grasping the heel.