The Collaborative International Dictionary of English v.0.48:

Saintliness \Saint"li*ness\, n.
   Quality of being saintly.
   [1913 Webster]

WordNet (r) 3.0 (2006):

saintliness
    n 1: the quality of resembling a saint

Moby Thesaurus II by Grady Ward, 1.0:

39 Moby Thesaurus words for "saintliness":
   Christianity, Christlikeness, Christliness, angelicalness,
   beauty of holiness, fear of God, godlikeness, godliness,
   godly-mindedness, goodness, heavenliness, heavenly-mindedness,
   holiness, holy-mindedness, moral rectitude, morale, morality,
   odor of sanctity, otherworldliness, probity, pureness,
   pureness of heart, purity, rectitude, right conduct, righteousness,
   sainthood, saintlikeness, saintship, sanctitude, sanctity,
   seraphicalness, spiritual-mindedness, spirituality, unearthliness,
   unworldliness, virtue, virtuousness, worthiness