Job 28:5

As for the earth, out of it cometh bread: and under it is turned up as it were fire.

As for the earth, out of it cometh bread,.... That is, bread corn, or corn of which bread is made particularly wheat; which falling, or being cast into the earth, rises up and brings forth fruit, and, when ground into flour, makes fine bread; and to this same original the psalmist ascribes bread, which strengthens man's heart, Ps 104:14. The West Indians formerly made their bread of roots of the earth, particularly one called "jucca" {b}; so Caesar's soldiers in distress made bread of a root called "chara", steeped in milk {c}:

and under it is turned up as it were fire; coal, which is fuel for fire; for, as in the earth are mines for gold and silver, iron and brass, out of which they are dug, or the ore of them, so there is coal under the earth; which, when turned up, or dug, is taken for firing; or brimstone, or sulphureous matter, which is easily inflammable; and sometimes the same earth, the surface of which is covered with corn, out of which bread cometh, underneath are coal, or sulphur, and such like combustible matter: some think precious stones are meant, which glitter and sparkle like fire; see Ezekiel 28:14.

{b} P. Martyr, Decad 1. l. 1.
{c} Caesar. Comment. Bell. Civil. l. 3. c. 48.