E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
Heart of Grace (To take).
To pluck up courage; not to be disheartened or down-hearted. This expression is based on the promise, “My grace is sufficient for thee” (2 Cor. xii. 9); by this grace St. Paul says, “When I am weak then am I strong.” Take grace into your heart, rely on God’s grace for strength, with grace in your heart your feeble knees will be strengthened. (See HART OF GREASE.)
