"wholehearted devotion" is correct and can be used in written English.
You can use it to describe unwavering commitment or dedication to a cause or person. For example, "John was full of admiration for his wife's wholehearted devotion to their children."
A second Roman element in Latini's legacy to become an important part of Dante's culture was the love of glory, the quest for fame through a wholehearted devotion to excelling.
To do his part, Goldwater, with coaching from the lawyerly Nixon, wrote out a fresh translation of those two sentences in his acceptance speech: "If I were to paraphrase, I would do it by saying that wholehearted devotion to liberty is unassailable and that half-hearted devotion to justice is indefensible".
As part of our prayers, Yvonne Lyon sings about a prayerful response which expresses our wholehearted devotion to the Lord.
I repeat once more that I think this Nation's greatest security lies, not in trusting to a momentary majority of this Court's view at any particular time of what is "patently arbitrary," but in wholehearted devotion to and observance of our constitutional freedoms". Political history surrounds the power of Congress to create Social Security.
And you, my son Solomon, acknowledge the God of your father, and serve him with wholehearted devotion and with a willing mind, for the Lord searches every heart and understands every motive behind the thoughts.
Paryushana ("Abiding") designates, on the one hand, pacification by forgiving and service with wholehearted effort and devotion and, on the other, staying at one place for the monsoon season.
Her debut release was plain startling in the era of Garth Brooks and the Dixie Chicks: a quietly wholehearted homage to the simpler virtues of 40s and 50s country music, executed with devotion and grace.
His devotion to the details of lace and gauze for his friend George Montagu is clearly wholehearted, though his delight in shopping - "is there greater happiness?" - is surely too knowingly camp to have been typical.
He laughed with wholehearted gusto.
It means "total devotion".
This devotion is sincere.
