John Trapp on Job 18:12

Verſe 12.Fit famelicum robur ejus. His ſtrength ſhall be hunger-bitten] Heb. His ſtrength (or wealth) ſhal be famine. Or, Famine ſhall be his ſtrength. He, who whilom having health and wealth at will, fared deliciouſly and gathered ſtrength, ſhall be hunger-ſtarved, and hardly have priſoners pittance; ſo much only as will neither keep him alive, nor ſuffer him to dye. See 1 Sam. 2.5.36. 'Tis as much, faith Brentius, as we uſe to ſay of an extreme poore or feeble perſon, his wealth is poverty, his ſtrength weakneſſe.

And deſtruction ſhall be ready at his ſide] i.e. Shall ſuddenly and inevitably ſeize upon him, there will be no running away from it, for can a man run from his ſide? The word ſignifieth not an ordinary calamity, but a dreadful and direful deſtruction. Some underſtand it of the Pluriſie, or Ʋlcers in the ſide of a man: Others of ribroſt, as they call it, tortures inflicted on condemned perſons (as Heb. 11.34) who are beaten with bats.