Inexcusable
From BiblePortal Wikipedia
King James Dictionary [1]
Inexcu'Sable, a. s as z. L. inexcusabilis in and excusabilis, excuso. See Excuse. Not to be excused or justified as inexcusable folly.
Webster's Dictionary [2]
(a.) Not excusable; not admitting excuse or justification; as, inexcusable folly.