Peter of Alexandria, Ante-Nicene Fathers Vol. VI, Canonical Epistle… (1885)
“ Conformably to the sixty-fourth Apostolical canon, which decrees that we are not to fast on the Sabbath, with one exception, the great Sabbath; and to the sixty-ninth canon, which severely punishes those who do not fast in the Holy Lent, and on every fourth day of the week and day of preparation. Thus also does the present canon decree.Zonaras. Always, says he, are the fourth and sixth days of every week to be kept as fasts; nor will any one find fault with us for fasting on them ”
