saving grace in WordNet English dictionary

1. (Christian theology) a state of sanctification by God; the state of one who is under such divine influence
   "the conception of grace developed alongside the conception of sin"; "it was debated whether saving grace could be obtained outside the membership of the church"; "the Virgin lived in a state of grace"
   grace  saving grace  state of grace 
   
2. a redeeming quality or characteristic
   "her love of music remains her one saving grace"; "her sense of humor has to be a saving grace"; "the saving grace for both developments is that they are creating jobs"
   saving grace 
   

saving grace in English Wiktionary