יֹ֭אכַל בַּדֵּ֣י עוֹר֑וֹ יֹאכַ֥ל בַּ֝דָּ֗יו בְּכ֣וֹר מָֽוֶת׃
It shall devour the members of his body, Yea, the first-born of death shall devour his members.
Rashi on Job
He shall eat the branches of his body And he shall devour all the rest of his branches, viz. his sons and daughters.
Rashi on Job
the prince of death Heb. בכור מות, as in (Ps. 89:28), “Also I will make him a prince (בכור).”