If you have no works, do not speak on virtues. Afflictions suffered for the Lord’s sake are more precious to Him than every vow and sacrifice; and the odour of their sweat surpasses every fragrance and choice incense. Regard every virtue performed without bodily toil as premature, stillborn fruit of the womb.

The Ascetical Homilies of Saint Isaac the Syrian, I, 6, translated by the Holy Transfiguration Monastery, Boston, 1984. 60.