A Voice from the Past - Gregory of Nazianzen

For a bad man would speedily condemn even a good man, while a good man would not be ready to condemn even a bad one.

Gregory of Nazianzen, 330-390 AD, Select Orations, On the Great Athanasius, 15 (translated by Charles Gordon Browne and James Edward Swallow, Nicene and Post-Nicene Fathers, Philip Schaff and Henry Wace, T &; T Clark and Wm. Eerdmans Publishing, 1996, Second Series, Vol. VII, p. 273).

Is this true? How do we avoid being those who too easily condemn?