When the summon finally comes

The physician, with his medical art and his drugs, Cannot avert a summons that has come, What ails the physician that he dies of the disease That he would have cured in time gone by? There died alike he who administered the drug and he who took it, And he who imported and sold the drug, and he who bought it.

Verses upon the death in Baghdad of the physician Yuhanna ibn Masawayh in 857