Can the Church Impose a Fast?
While all Christians agree that fasting should be part of our spiritual lives, there are many (mostly Protestants) who believe that the Church goes too far when she imposes a fast on the Christian people, such as during Lent. The Lord Jesus clearly expected His followers to fast (Matt 6:16), and the early Church certainly met this expectation (Acts 13:2-4, 14:23), however, did Jesus ever give the Church the authority to enforce a particular kind of fasting, under pain of mortal sin no less? I would argue that He did.
Consider Hebrews 13:17, “Obey your rulers and submit to them, for they are keeping watch over your souls.” According to St. Paul, Christians have a divine obligation to obey their ecclesiastical rulers for the sake of protecting their own souls. This would imply that the Church’s hierarchs have the authority to impose spiritual discipline on their flocks, and when they do, Christians must obey. Obviously, if a hierarch commands something contrary to God’s Law then the obligation to obey dissipates, however, fasting periodically in accordance with your ability is not contrary to God’s Law. Thus, when the Church prescribes something like the Lenten fast, or the Wednesday and Friday fast, Christians must heed the command to “obey your rulers and submit to them.” In fact, based on Didache 7, it could even be argued that prescribed fasting came from the apostles themselves, meaning that their successors, the bishops, may issue similar decrees.
Furthermore, in order to understand why disobeying the Church’s laws could result in mortal sin, consider Romans 13:1-2, “Let every person be subject to the governing authorities. For there is no authority except from God, and those that exist have been instituted by God. Therefore whoever resists the authorities resists what God has appointed, and those who resist will incur judgment.” Clearly, St. Paul expects Christians to obey the civil authorities as those who have been appointed by God, and he even goes so far as to suggest that disobeying the state is akin to disobeying the Lord Himself. Paul further says that the civil magistrate is “an avenger who carries out God’s wrath on the wrongdoer” (Rom 13:4), once again affirming that the state acts with divine authority. With this in mind, what do you think would happen if the state imposed a kind of fast on its subjects? What if, say, everyone under twenty one had to fast from alcohol until they were of age? There is no divine law that states that those under twenty one cannot drink, and so it is not intrinsically immoral, however there is a divine law to obey the civil authorities. As such, to disobey them when they are not commanding something unjust would be mortally sinful. So it is with the ecclesiastical authorities.
This is especially the case when we consider that, unlike civil rulers whose authority is ordered towards God’s justice, the authority of ecclesiastical rulers is ordered towards the salvation of God’s people. The Church’s hierarchs are given authority so that they might keep watch over the souls of Christians (Heb 13:17), bring them to salvation (1 Cor 5:5 cf. 11:32), and build up Christ’s body in love, “so that we may no longer be children, tossed to and fro by the waves and carried about by every wind of doctrine” (Eph 4:12-14). Given how important this ministry is for the salvation of souls, it is no wonder that Christ promised to be with His chosen apostolic ministers “until the close of the age” (Matt 28:20), a promise that, since the apostles’ deaths, must carry on in the persons of their successors. Indeed, the Lord Jesus made sure to note that the very Church that has the authority to exercise discipline on her members (Matt 16:19), is the one against whom the gates of Hades will never prevail (Matt 16:18). For our purposes, I believe this famous Matthean text is worth pausing on for a moment.
In the Sermon on the Mount, the Lord Jesus spoke of “a wise man who built his house on the rock” (Matt 7:24). When the rain fell, the floods came, and the wind blew on that house, “it did not fall, because it had been founded on the rock” (Matt 7:25). Later in that same Gospel account, it seems the Lord heeded his own wisdom. In Matthew 16:17-19, Jesus built His house on the rock of St. Peter and promised that “the gates of Hades shall never prevail against it.” This clearly has the same intended meaning as Matthew 7:24-25, namely, the reason why the house will always stand is because it is built on the rock. In other words, because Jesus made St. Peter the rock of His Church, somehow, this explains why the gates of Hades will never prevail. What, in context, could ensure that Peter will be a firm foundation of the Church for all ages? It must be his possession of “the keys of the kingdom of heaven,” with which he can “bind” and “loose” on earth and in heaven (Matt 16:19) for the salvation of God’s people. As such, when the Church wields this very “power of the keys” to impose discipline on God’s people for the salvation of their souls, we can be confident that Christ Himself stands behind these decrees, ensuring that none of them will cause the Church to fail her divinely appointed mission to save souls.
Thus, since the Church (unlike the state) exercises her spiritual authority with special divine protection, Christians ought to unquestioningly heed those ecclesiastical laws laid down for our salvation, such as required fasting. Indeed, this belief that the Church speaks with the voice of God when she universally commands the faithful to observe a liturgical season like Lent has been held by our Christian forbearers for millennia, so who are you to call it into question? Even if your questioning were valid, why take that risk? I believe everyone would be much safer wagering on the side of historic Christianity, rather than any later reconstructions of the faith that claim to have finally gotten it right.