We must not esteem by pretending to esteem; but we should in truth think it possible for another person to have something that is hidden to us and whereby he is better than we are, although our own good whereby we are apparently better than he, be not hidden.
 Thomas Aquinas, Summa Theologica (1274). copy citation

add
Author Thomas Aquinas
Source Summa Theologica
Topic truth hiding
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/18755/pg18755-images.html

Context

“If we set what our neighbor has of God's above that which we have of our own, we cannot incur falsehood. Wherefore a gloss [*St. Augustine, QQ. lxxxiii, qu. 71] on Phil. 2:3, "Esteem others better than themselves," says: "We must not esteem by pretending to esteem; but we should in truth think it possible for another person to have something that is hidden to us and whereby he is better than we are, although our own good whereby we are apparently better than he, be not hidden." Reply Obj. 3: Humility, like other virtues, resides chiefly inwardly in the soul. Consequently a man, by an inward act of the soul, may subject himself to another, without giving the other man an occasion of detriment to his spiritual welfare.” source