Do not condemn your brother nor call his cowardice wrong, do not be quick to accuse him or reject him, while you profess to be meek! Show your humility wherever possible, and place your brother’s interests before your own and you will do no harm. For to condemn and scorn him is to separate him from Christ and his only hope, and is equivalent to cutting down together with the darnel the hidden wheat, which may be more precious than you are.
On the contrary, when you correct him – with kindness and love, not like an enemy or a harsh doctor who knows nothing but cauterising and cutting – at the same time recognise yourself and your own weakness.
What happens in fact when you suffer from watery eyes, or some other visual impairment, and you cannot see the sun clearly? And when you see everything spinning around because you have vertigo or are drunk, do you blame someone else? You have to reflect and suffer much before condemning someone else of impiety!
Saint Gregory of Nazianzen
Discorso sulla moderazione nel disputare
La teologia dei Padri/4, Città Nuova, Roma 1975, p. 126