But after that the kindness and love of God our Saviour toward man appeared, Not by works of righteousness which we have done, but according to his mercy he saved us, by the washing of regeneration, and renewing of the Holy Ghost;
Exodus 34:6-7
And the LORD passed by before him, and proclaimed, The LORD, The LORD God, merciful and gracious, longsuffering, and abundant in goodness and truth, Keeping mercy for thousands, forgiving iniquity and transgression and sin,
Paul's 'kindness and love of God... according to his mercy' invokes the Exodus 34 divine name-proclamation as the constitutional character foundation for salvation. The Sinai self-disclosure established kindness, mercy, longsuffering, and goodness as the LORD's constitutional character attributes. Paul grounds salvation not in human righteousness but in the LORD's mercy — the same Exodus 34 mercy that Moses encountered on the mountain is the constitutional basis for the redemption that appeared in the fullness of time.