Feb 26 2009
Aquinas On Why We Fast
1. We fast for three reasons.
(a) To check the desires of the flesh:
First, in order to bridle the lusts of the flesh, wherefore
the Apostle says (2 Cor. 6:5, 6): “In fasting, in chastity,” since
fasting is the guardian of chastity. For, according to Jerome
[*Contra Jov. ii.] “Venus is cold when Ceres and Bacchus are not
there,” that is to say, lust is cooled by abstinence in meat and
drink.
(b)we have recourse to fasting in order that the mind
may arise more freely to the contemplation of heavenly things: hence
it is related (Dan. 10) of Daniel that he received a revelation from
God after fasting for three weeks.
(c)Thirdly, in order to satisfy for
sins: wherefore it is written (Joel 2:12): “Be converted to Me with
all your heart, in fasting and in weeping and in mourning.” The same
is declared by Augustine in a sermon (De orat. et Jejun. [*Serm.
lxxii] (ccxxx, de Tempore)): “Fasting cleanses the soul, raises the
mind, subjects one’s flesh to the spirit, renders the heart contrite
and humble, scatters the clouds of concupiscence, quenches the fire
of lust, kindles the true light of chastity.”
2. There is a command laid upon us:
Now it has been stated above (A. 1) that fasting is useful as atoning
for and preventing sin, and as raising the mind to spiritual things.
And everyone is bound by the natural dictate of reason to practice
fasting as far as it is necessary for these purposes. Wherefore
fasting in general is a matter of precept of the natural law, while
the fixing of the time and manner of fasting as becoming and
profitable to the Christian people, is a matter of precept of
positive law established by ecclesiastical authority: the latter is
the Church fast, the former is the fast prescribed by nature.
3. fasting is directed to two things:
the deletion of sin, and the raising of the mind to
heavenly things. Wherefore fasting ought to be appointed specially
for those times, when it behooves man to be cleansed from sin, and
the minds of the faithful to be raised to God by devotion: and these
things are particularly requisite before the feast of Easter, when
sins are loosed by baptism, which is solemnly conferred on
Easter-eve, on which day our Lord’s burial is commemorated, because
“we are buried together with Christ by baptism unto death” (Rom.
6:4). Moreover at the Easter festival the mind of man ought to be
devoutly raised to the glory of eternity, which Christ restored by
rising from the dead, and so the Church ordered a fast to be observed
immediately before the Paschal feast; and for the same reason, on the
eve of the chief festivals, because it is then that one ought to make
ready to keep the coming feast devoutly.-From the Summa Theologica, II, Q.147, art., 1, 3, 5,
