“ wherefore a man is not always more ashamed of a more grievous sin, but of a viler sin. ”
 Thomas Aquinas, Summa Theologica (1274). copy citation

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“Hence flattery, through being accompanied by deceit, seems to be a viler sin; while quarreling, through proceeding from greater contempt, is apparently more grievous. Reply Obj. 3: As stated in the objection, shame regards the vileness of a sin; wherefore a man is not always more ashamed of a more grievous sin, but of a viler sin. Hence it is that a man is more ashamed of flattery than of quarreling, although quarreling is more grievous. _______________________ QUESTION 117 OF LIBERALITY (In Six Articles) We must now consider liberality and the opposite vices, namely, covetousness and prodigality.” source