Our friend Durandus’ commentary on the Masses of the three days after Ash Wednesday explains that they treat of prayer (Thursday), fasting (Friday), and almsgiving (Saturday) respectively. The section for today (book VI, 31) is fairly obscure, and my translation is really more of a paraphrase.
On Saturday, the Church treats of almsgiving and of the Sabbath (Latin ‘sabbatum’), because by the three things aforementioned, namely, prayer, fasting and almsgiving, one comes to the Sabbath rest, (Latin ‘sabbatismus’), where the satisfaction for sin has been made, and peace comes together with the Sabbath rest. Wherefore the epistle (Isaiah 58, 9-14), which begins with the words, “If thou wilt take away the chain that is in thy midst”, goes on to say, “thou shalt call the Sabbath delightful.”
The Gospel (Mark 6, 47-56) says the same thing, where it speaks of the disciples laboring upon the sea. who signify those who are penitent. The Lord gets into the ship with them, and the sea is immediately calmed, for when the Lord is present in a man’s heart, his soul is made peaceable, and he becomes calm. ... Today we fast, that we may come to the Sabbath of eternal rest.
