Surety

"For Luther, as for the reformers in general, one could rest assured of one's salvation. Salvation was grounded upon the faithfulness of God to his promises of mercy; to fail to have confidence in salvation was, in effect, to doubt the confidence in God, untroubled by doubt. Faith is not the same as certainty, although the theological foundation of Christian faith may be secure, the human perception of and commitment to this foundation may waver."
(Alister E. McGrath, Historical Theology: An Introduction to the History of Christian Thought, 194)

Hear ye, hear ye: feelings lie sometimes.