Kindness does not mean overlooking people’s sins; it means forgiving them. Kindness also does not mean “being nice” to everyone whoever they are and whatever they do. It does not mean “going along” with others in every way. A kind person will correct others, if need be, and his very kindness will be shown by his care and concern for the well-being of his fellow creature “for whom Christ died” (Rom 14.15).
(Fr. Thomas Hopko, The Orthodox Faith Vol. 4 Spirituality, p. 85)