You know that decent penitence accompanied by tears that spring from the depth of the heart will melt and burn away the filth of sin. Light a fire and make pure the soul that has been defiled. In addition, penitence through the visitation of the Spirit generously imparts an abundant flow of light to the soul, whereby it is filled with mercy and good fruits (James 3:17). I pray, therefore, fathers and brethren, let us use fasting both during this third week of Lent and in those that follow, as we daily add fervor to fervor and zeal to zeal, until we arrive at the Sunday of Easter with souls and bodies alike resplendent. St. Symeon the New Theologian, The Discourses, Page 174
If you want to read more about St. Symeon, I wrote about my love for St. Symeon and his writings here.