withsake
To forsake; abandon; renounce; deny; refuse.
obsolete, transitive
Well! the king then openly declared to the priest and to them all, that he would firmly "withsake" and renounce idolatry, and receive the faith of Christ.
Where it comes from
From Middle English withsaken, from Old English wiþsacan (“to forsake, abandon, renounce, refuse, deny, oppose, drive against”); equivalent to with- + sake. Compare Middle High German widersachen.
Adapted from the Wiktionary entry withsake (CC BY-SA 4.0).