E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Isenbras or Sir Isumbras.
A hero of mediæval romance, first proud and presumptuous, when he was visited by all sorts of punishments; afterwards penitent and humble, when his afflictions were turned into blessings. It was in this latter stage that he one day carried on his horse two children of a poor woodman across a ford. (See YSAMBRAS.)