This is it that is loved in friends; and so loved, that a man's conscience condemns itself, if he love not him that loves him again, or love not again him that loves him, looking for nothing from his person but indications of his love.
 Saint Augustine, Confessions (401). copy citation

add
Author Saint Augustine
Source Confessions
Topic love conscience
Date 401
Language English
Reference
Note Translated by E. B. Pusey
Weblink http://www.gutenberg.org/files/3296/3296-h/3296-h.htm

Context

“These and the like expressions, proceeding out of the hearts of those that loved and were loved again, by the countenance, the tongue, the eyes, and a thousand pleasing gestures, were so much fuel to melt our souls together, and out of many make but one. This is it that is loved in friends; and so loved, that a man's conscience condemns itself, if he love not him that loves him again, or love not again him that loves him, looking for nothing from his person but indications of his love. Hence that mourning, if one die, and darkenings of sorrows, that steeping of the heart in tears, all sweetness turned to bitterness; and upon the loss of life of the dying, the death of the living. Blessed whoso loveth Thee, and his friend in Thee, and his enemy for Thee.” source