King James Dictionary

Gainsay To answer; to speak against. but before all these, they shall lay their hands on you, and persecute you, delivering you up to the synagogues, and into prisons, being brought before kings and rulers for my name's sake. And it shall turn to you for a testimony. Settle it therefore in your hearts, not to meditate before what ye shall answer: for I will give you a mouth and wisdom, which all your adversaries shall not be able to GAINSAY nor resist. (Luk 21,15)