To be wholehearted is to walk with courage into that which matters. The word Courage itself means to be "of the heart", derived from the Latin word "_cor_".
Commitment means that that we deeply and passionately care.
The very first principle of the Agile Manifesto is about this commitment:
>Our highest priority is to satisfy the customer ...
It then talks about software:
> ... through early and continuous delivery of valuable software.
But, over time, this commitment became more than about software as Agile became more than about software development.
To understand Agile, one must truly understand the radical nature of this first principal. First a foremost, what matters is the customer, not the company profitability, known as "shareholder value".
And equally radical is when this commitment is applied to education, where each student becomes the focus, not the test scores. In Jimmy Casas' words , "Every student, every day, whatever it takes".
A non-negotiable, heart-centered, commitment.