Kenyon is related to New Thought- a stream from which flows Christian Science and Unity. It is NOT Christian or biblical at its root/heart/ foundation but has used Christian words to describe something else. I believe it is a stream that came forth during a real move of the Holy Spirit to counterfeit, pervert, and in some cases, pre-empt the real deal.
Instead of starting with WOF ideas/theology...lets start with the Word of God in which the focus is not - what I get- but knowing God more, Him being glorified, HIS will being done... The Lord's prayer is so far away in tone and substance from many of the WOF prayers....
I do believe that healing is for today and in the present gifts and ministry of the Holy Spirit as being a VITAL part of our walk. But what is the purpose of these gifts and ministry? To edify...to build up ourselves and one another.
The WOF - healing focus really brings one into a SELF or PROBLEM centered focus...
When I was not being healed of things, I'd wonder if I was saved. When others were healed...or experienced answered prayer- I'd feel JEALOUS. (!!) Like a little kid- why them Lord and not me? ! Very self centered....
Researching the roots/history of New Thought/WOF was helpful to me and I recommened it along with Christianity in Crisis by Hank Hannegraff. I'm hoping he is not "throwing the baby out with the bathwater" but so far it seems pretty solid.
Google "ex word of faith" "ex word of faith preacher' ....There are many spiritually, physically and emotionally hurt people in this movement- and worse, people who have lost faith in the real Jesus.
But to your question...what IS biblical?
Our words are important...because it affects other people. We can encourage them or destroy them with criticism. This is love...Versus a source of spiritual power.
It's about the heart. Simon the magician wanted the power of the Holy Spirit for the wrong reasons... Speaking affirmations and such... I believe that this is New Age....I really don't see this idea conveyed consistently through the NT. I personally believe it's a form of witchcraft. It's one thing to say something because you know and believe it...from the heart. It's quite another to simply confess dozens of statements....even good and biblical things IF YOU DON'T REALLY BELIEVE OR KNOW IT...in order to MAKE IT HAPPEN THROUGH YOUR SPEECH.