How long should I fast before receiving Holy Communion?

It is common to hear nowadays that one need only fast for an hour before the reception of Holy Communion. While this is technically true, is it the mind of the Church? To understand the question we first need to understand what fasting is and then how it pertains to one's reception of Holy Communion.

First, most basically, to fast is to abstain from food or drink for a certain period of time. The Latin word ieiunium refers to a part of an animal's intestine that is always empty. This denial of the desire for food - closely connected to the desire for sex - is an apostolic and perennial part of the Church's life and discipline. Already in the Acts of the Apostles (13:2) we find the practice of fasting connected to the Christian Liturgy and therefore the Biblical basis for the Church's mandatory Eucharistic fast. " While they were worshiping the Lord and fasting, the Holy Spirit said, "Set apart for me Barnabas and Saul for the work to which I have called them." (Acts 13:2)


The Church's local and ecumenical Councils from the very beginning taught that only those fasting may celebrate and receive the Lord's Body and Blood so as to show the priority of the Lord's food over earthly food and to eradicate any possibility of the shameful practices of the early Corinthian community. (1 Cor 11: 17-33) Saint Augustine elucidates the reasons in a most concise and perfect manner: "It has pleased the Holy Ghost that, to honor so great a Sacrament, the Lord's Body should enter the mouth of the Christian before other food." (St. Augustine, Ep. 54, , cap. 6: , PL, 33, 203)

The canonical tradition of the Church clear demonstrates the seriousness with which the Church takes the Eucharistic fast. The Venerable Pius XII in his Apostolic Constitution Christus Dominus teaches: "The solicitude of the Church for the preservation of the Eucharistic fast may be perceived also from the fact that the Church, in decreeing this fast, imposed serious penalties for its violation. Thus the Seventh Council of Toledo in the year 646 threatened with excommunication anyone who should say Mass after having broken his fast.[13] In the year 672 the Third Council of Braga,[14] and in the year 685 the Second Council of Macon[15] had already pronounced that anyone who incurred this guilt should be deposed from his office and deprived of his honors."

It wasn't until November 21, 1964 that Pope Paul VI reduced the Eucharistic fast to one hour. Finally there is an interesting addition that was made in the second schema to the 1983 Code of Canon Law which continued through and remains in the final edition of the Code. The Canon reads as follows: "One who is to receive the Most Holy Eucharist is to abstain from any food or drink, with the exception of water and medicine, for at least the period of one hour before Holy Communion." (The Code of Canon Law, Canon 919) For at least one hour… This "saltem" clause rather nicely articulates the proper hermeneutic of this question in line with Pius XII and Paul VI. One is permitted to receive having only fasted for an hour but one is encouraged to keep the traditional fast from midnight if possible or the three hour fast for a legitmate reason. The spiritual benefits and reasons for the traditional and immemorial fast retain all of their relevance and value.

For further reading, please read The Venerable Pius XII's Christus Dominus.