What is Grace?

Legal Definition
That which a person is not entitled to by law, but which is extended to him as a favor; a pardon, for example, is an act of grace. There are-certain days allowed to a payer of a promissory note or bill of exchange, beyond the time which appears on its face, which are called days of grace. (q. v.)
-- Bouviers Law Dictionary
Legal Definition
This word is commonly used in contradistinction to "right." Thus, in St 22 Edw. III., the lord chancellor was instructed to take cognizance of matters of grace, being such subjects of equity jurisdiction as were exclusively matters of equity. Brown. A faculty, license, or dispensation; also general and free pardon by act of parliament. See Act op Grace.
-- Black's Law Dictionary
Legal Definition
See Days of grace.
-- Ballentine's Law Dictionary