Saint Poemen the Great was asked, ‘What is faith?’ The great man replied that faith consists in remaining in humility and showing mercy; that is to say, in humbling oneself before one’s neighbors and forgiving them all discourtesies and offenses, all their sins.
As foolish zealots make out that faith is the prime cause of their zeal, let them know that true faith, and consequently also true zeal, must express themselves in humility regarding our neighbors and in mercy towards them. Let us leave the work of judging and convicting people to those persons on whose shoulders is laid the duty of judging and ruling their brethren.
‘He who is moved by false zeal,’ says Saint Isaac the Syrian, ‘is suffering from a severe illness. O man, you who think to use your zeal against the infirmities of others, you have renounced the health of your own soul! You had better bestow your care on the healing of yourself, and if you want to heal the sick, know that the sick need nursing, rather than reprimand. But you, instead of helping others, cast yourself into the same painful illness. This zeal is not counted among men as a form of wisdom, but is one of the diseases of the soul, and as a sign of narrow-mindedness and extreme arrogance.
The beginning of divine wisdom is quietness and meekness, which is the basic state of mind proper to great and strong souls and which bears human weaknesses. Ye that are strong ought to bear the infirmities of the weak (Rom. 15:1), says Scripture.
And again: Restore a sinner in the spirit of meekness and gentleness (see Gal.6:1). The Apostle counts peace and patience (Gal. 5:22) among the fruits of the Holy Spirit.
Not to judge, but not to commune with the heretics: