A mistake frequently made in writing is to say that someone “did not waiver” in their faith, or from a decision they had made.  What they really mean is that the person in question did not waver. 

Once again, it is a failure to choose between differently spelled homophones that is the problem here. 

Waiver: the renunciation or surrendering of  ownership, a right  or a claim
Example: The council decided to waive the annual fee for dog registration. The waiver resulted in more households registering  their pets. 

Waver: to hesitate or falter, or to flicker, quiver or tremble.
Examples: Her feelings for him wavered between passionate love and indifference. 
He did not waver in his support for the mayor, who was a woman of integrity. 
The flame of the candle wavered in the gentle breeze.

At least when one waves at the waves, the spelling is the same so you can’t get it wrong!