Faith Is Assurance (3): Q. 21 of the Heidelberg Catechism

Faith is assurance. Faith is assurance of personal salvation. Faith is assurance that the one who, from the heart, believes the gospel is saved now, has been saved from eternity in the decree of election, and will be preserved unto everlasting salvation. Faith is absolute certainty of personal salvation, the only kind of certainty that is certain. A certainty that is not absolutely certain is, in fact, uncertainty, that is, doubt. Such "certainty" is worthless. Assurance belongs to the...