The faith and piety of souls, no doubt, remain, but this should be made known by the evidence of a letter, in order that an increase of affection may be gained by such mutual courtesy. For just as a fertile field cannot bring forth abundant fruits, if its cultivation has been neglected, and the good qualities of soil are lost through the indolence of one who rests, instead of working, so I think that the love and kindly feelings of the mind grow feeble, unless those who are absent are visited, as if present, by means of a letter.1