Before receiving Holy Communion a Catholic abstains from all food and drink except water and medicine for one hour. That hour was, until 1953, a fast from the previous midnight — which is the single clearest example on this site of a discipline moving.
“One who is to receive the Most Holy Eucharist is to abstain for at least one hour before Holy Communion from any food and drink, except only water and medicine.”
Whom it binds
- ·One hour before receiving Communion, not one hour before Mass begins.
- ·Water and medicine never break the fast, at any period of the law.
- ·The elderly, the infirm, and those who care for them may receive even if they have eaten within the hour.
- ·A priest celebrating a second or third Mass in a day need observe only the hour before each.
How the rule has moved
Watching a law change is the fastest way to learn it was never dogma.
- c. 393
The Council of Hippo requires that the sacrament of the altar be offered only by those who are fasting — the custom becoming law. The Third Council of Carthage repeats it in 397 in the same words.
Council of Hippo (393), canon 29; Third Council of Carthage (397), canon 28 - 1917
The Code binds a complete fast from all food and drink, including water, from the preceding midnight.
1917 Code of Canon Law, canon 858 - 1953
Pius XII permits water at any time and reduces the fast to three hours for solids and one for liquids, chiefly so that evening Mass becomes possible for working people.
Apostolic constitution Christus Dominus, 6 January 1953 · read it - 1957
Pius XII extends the three-hour fast to all Masses, morning as well as evening.
Motu proprio Sacram Communionem, 19 March 1957 · read it - 1964
Paul VI reduces the fast to one hour for everyone.
Announced at the Second Vatican Council, November 1964; codified in the 1983 Code, canon 919
Why the midnight fast ended
The midnight fast was not abandoned because reverence declined. It was abandoned because it had begun to prevent Communion altogether. Under the 1917 law, Mass could not practically be celebrated in the evening: a priest and congregation who had not eaten or drunk since midnight could not be asked to fast through a working day. That meant no evening Mass, which meant that industrial workers, night-shift labourers, and much of the developing world could not attend Mass at all except on Sunday morning, if then.
Pius XII's mitigation in 1953 was written for exactly those people, and the constitution says so — it names the conditions of modern work, and the situation of Catholics in mission territories and behind the Iron Curtain. The change was not a lowering of standards but a choice between two goods, made in favour of people receiving Communion.
One hour, honestly kept
An hour is not much. It is short enough that most people clear it without noticing, which has a cost of its own: a discipline that is never felt teaches nothing. Many Catholics keep a longer fast voluntarily — three hours, or from midnight on a Sunday — and the Church has never discouraged it.
The point of the hour, whatever its length, is unchanged from the fourth century: that the first thing to enter the body that day should be the Lord. Everything else in the law is arrangement.
Where it gets mistaken for doctrine
Shortening the fast shows the Church stopped believing in the Real Presence.
The same pope who cut the fast to three hours, Pius XII, wrote Mediator Dei and Haurietis Aquas and defined the Assumption. The change was made so that more people could receive the Real Presence, not fewer.
Breaking the hour means you cannot receive.
If you realise at the altar rail that you drank coffee fifty minutes ago, the right course is ordinarily to abstain — but the law itself excuses the sick, the elderly and their carers outright, and the obligation has never been treated as a trap.
Why it matters
- ◇It puts a small, deliberate emptiness before the one thing that fills it.
- ◇It is the discipline most obviously arranged around people rather than around itself — the law bent so that a night-shift worker could receive.
- ◇Keeping more than the hour is entirely permitted, and is one of the easiest ways to make an ordinary Sunday deliberate.
Follow it further
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