Stress and Grace
Although William Hazlitt's definition of grace doesn't use the word stress, he is describing grace as the opposite of stress. Instead of writing that "grace is the absence of everything that indicates pain or difficulty, hesitation or incongruity," he could have written "grace is the absence of stress."
The word grace has a range of meanings in English, originating in its ancestors, the Latin gratia and the Old French grace. The Latin connotations included "favor, esteem, regard, pleasing quality, good will, gratitude." Old French meanings included "pardon, divine grace, mercy; favor, thanks, elegance, virtue." The English word grace inherited all of these wide-ranging definitions from its Latin and Old French ancestors. What meaning of grace can best enable you to turn stressed-out into peaceful?
The connotation of grace as favor is the meaning used by Christian theologians to develop a theology of grace. In Christian theology, grace refers to God's forgiveness and acceptance of you despite your sins. This is the connotation behind such statements such as: "There but for the grace of God go I." This definition makes grace an undeserved gift you receive rather than a quality you possess. This is not the perspective of grace that I intend here.
Rather, let's focus on the particular connotation of grace as a pleasing quality. This meaning of grace refers to gracefulness, elegance, ease, and fluidity of motion. This is the grace of the elegant figure skaters who dazzle you with what looks like effortless flow as they glide across the ice.
This is also the meaning of grace in Hans Christian Andersen's well-known story, "The Ugly Duckling." Of all of the birds, the white swan is the one most known for its gracefulness as it glides through the water, with its long neck arched ever so elegantly.