This is the third segment completing the topic of fasting (see Fasting Part I and Part II).
St. Faustina said that if the Angels could envy, they would envy man for two reasons: the Eucharist and the capacity to suffer. Both are most intimate forms of communion with Jesus Christ. The ability to suffer for the sake of Jesus Christ and to suffer with Him is one of His greatest gifts to us (see Rom 5:3; 8:17; 2 Cor 1:5-6; Phil 1:29; 3:8-11; Col 1:24; Heb 2:10; 5:8, 1 Pt 2:19-21). Besides Holy Communion, perhaps the closest we can come to our Lord is in our sufferings, when we do so willingly and in union with Him.
Fasting trains us in this strange form of intimacy, and this training in the school of the Cross is real a necessity for the spiritual life. And this intimacy bears fruit, as St. Paul says; it is the sufferings of the whole Christ, the Mystical Body which must continue to suffer throughout all ages. Yet this suffering of the Body is raised by its Head to become redemptive for the reparation of sins and the building up of the Church (see Col 1:24). Our suffering becomes redemptive for us and for others, and so even if not of the same intensity as His Passion, the sufferings of our fasting during the Lenten season (and all of the time really) allows us to walk with Him a bit more closely and a bit more efficaciously.
Fasting, then, should be joyful but that does not mean it is easy. Simply because we struggle with it and we may be tempted to see it as too much for us does not mean it is not good for us, or that it is impossible. St. Paul’s description of pommelling the body gives us a hint of this. Every habit, every virtue that we have to build whether it be aerobic capacity, muscular strength, intellectual acumen, or moral virtue does not seem in the initial stages to be a source of joy; in any case, it certainly is not pleasurable. However, if we persevere we will eventually enjoy its fruits. Perseverance is the key.
However, it is also true that we must not overdo our fasting. If Satan cannot tempt us with evil, he has no compunction against making recourse to the good. If we are enthusiastic about our fasting he will tempt us to excess, which can weaken and discourage us. As with every effort newly embarked upon, we should start small and work up to greater levels of self-mastery, but never to the point of doing damage to our health. Another danger to temptation with fasting is that of developing a sense of spiritual pride; a temptation to feelings of superiority over others who may not fast or may not be able to fast as strenuously as we have been able to achieve. Succumbing to such a temptation undermines the self-mastery we have gained and destroys the love, which was the end of the self-mastery in the first place.
The Church proposes a bare minimum for the public fast: one hour before receiving Holy Communion, abstinence from meat on every Friday of the year (though in the United States we may substitute some other penitential practice on Fridays outside of Lent) and in addition to abstinence, only one meal on Ash Wednesday and Good Friday (though being permitted two collations, or breakings of the fast, if necessary). Yet, we are invited, in a spirit of penitential joy, to add our own personal fasts during this most holy season…and so we joyfully must join together during this season, in mutual support and also understanding that we are all at different stages in the spiritual life, to make our personal Lenten fasts of those created goods to which we might be too attached (with the aim of keeping the newly acquired self-mastery after Lent).
Fasting should become fused with another of the Acts of Religion; namely prayer. Fasting should become a source of intimate prayer with our Lord and Savior, and it is to prayer that we shall next turn.