Kindness is not to be found in anything but that it adds to its beauty and it is not withdrawn from anything but it makes it defective. (Using translation from Muslim 2594a)
"إِنَّ الرِّفْقَ لا يَكُونُ فيِ شيءٍ إِلَّا زَانَهُ، وَلَا نُزع مِن شيءٍ إِلَّا شَانَهُ".