Правило 79 Василия Великого

One who goes berserk against his stepmother is subject to the same rule as one who goes berserk against his sister. (Basily Vel. 67, 75). Basil the Great equates a man who committed fornication with his stepmother to one who committed fornication with his sister, or to a murderer, and subjects him to twenty years of penance. You might be interested in: