I know that I have the ...

I know that I have the ability to achieve the object of my Definite Purpose in life, therefore, I demand of myself persistent, continuous action toward its attainment, and I here and now promise to render such action.
I know that I have the ability to achieve the object of my Definite Purpose in life, therefore, I demand of myself persistent, continuous action toward its attainment, and I here and now promise to render such action.

More phrases

If one does not know to which port one is sailing, no wind is favorable.
What a distressing contrast there is between the radiant intelligence of the child and the feeble mentality of the average adult.
We are masters of the unsaid words, but slaves of those we let slip out.
I have always found that mercy bears richer fruits than strict justice.
A lie gets halfway around the world before the truth has a chance to get its pants on.

Quotes from the same author

Effort only fully releases its reward after a person refuses to quit.
Bravery is fearlessness-the absence of fear. The merest dolt may be brave because he lacks the mentality to appreciate his danger.
Fears are nothing more than a state of mind.
Ideas are the beginning points of all fortunes.
You might well remember that nothing can bring you success but yourself.