Webster's Revised Unabridged Dictionary · 1913

Forefend

Forefend , transitive verb

[Old English forfenden; pref. for- + fenden to fend. See Fend, transitive verb]

To hinder; to fend off; to avert; to prevent the approach of; to forbid or prohibit. See Forfend.
God forefend it should ever be recorded in our history. — Landor
It would be a far better work... to forefend the cruelty. — I. Taylor