Why is the host unleaven?

Is it a matter of practicality or tradition?

So the Israelites in the OT made unleaven bread when fleeing from Egypt, because they didn’t have any time to lose.

I heard that yeast is a symbol of sin according to the Jews.

When Jesus broke the bread at the last supper was it also unleaven?

Yes it was, and it is for that reason we use unleavened bread in the Latin church. To use leavened bread for the Latin church would be seriously illicit.

It is NOT a precept of divine origin. Eastern churches of the Byzantine Rite, both Catholic and Orthodox, use leavened bread. For them to use unleavened bread would be seriously illicit for them.

In neither case would the Eucharist be invalid.

The Latin Church uses unleavened bread because that is what Jesus would have used, and I believe it is what the early Church used as well. The Eastern Churches, I believe (if I can paint them all with such a broad stroke) use leavened bread to symbolize the resurrection. Both are valid, but I think the Latin Church wouldn’t like the idea of one of their priests using leaven.

To answer your question, I would say it is tradition.

That seems to be the case. The gospels (Matthew 26:17; Mark 14:12; Luke 22:7) place the Last Supper on the first day of the seven-day festival of Unleavened Bread during which period the consumption of leavened bread was prohibited. (Exodus 12:15-20)

By the way, those Christians who use leavened bread when celebrating the Lord’s Supper could find support for that practice in the saying of Jesus, “The kingdom of heaven is like leaven which a woman took and hid in three measures of meal, till it was all leavened.” (Matthew 13:33; also see Luke 13:20-21)

It isn’t a matter of tradition because even Catholic scholars agree that originally the Eucharistic bread was leavened, in the east and the west.

Unleavened bread is the bread of people on a journey. There is no time for bread to be prepared with leaven when on a journey.

Christ instituted the Eucharist at a Seder meal. At a Seder, the bread is unleavened and is eaten with roast lamb, wine, and bitter herbs. The Eucharist and the sacrifice of the Mass is a re-presentation of that Seder meal, or as it is more popularly known, The Last Supper. Unleavened bread, wine, and the Lamb of God, veiled in that unleavened bread, is our meal signifying our journey with Christ to our promised land in the Kingdom of the Father.


Ignoring your “most scholars agree” argument for a moment, I have a number of thoughts.

First I concede that it is impossible to make wine without yeast. It will only be grape-juice. Historically one does not need to add yeast from the fridge to make wine, it is present naturally in the right place during harvest.

Second, how easy was it to make leavened bread historically. Nowadays I just reach into the fridge and pull out the container of “bread making yeast”. If I did not have that luxury at my disposal, how was leavened bread made in the past?

I’m pretty certain people left out a flour, sugar, and water mix to trap yeast from the air. So it’d sit out for a time. Then it could be needed and mixed together as a “starter dough.”

As Wesrock said, leaven at the time usually took the form of starter dough: a batch of dough from the previous day that went sour (sourdough) was kept and mixed with today’s batch. You would then use some of today’s dough to leaven tomorrow’s batch, and so on.

According to the Old Catholic Encyclopedia, there were actually some Churches who still made the Eucharistic bread via this method at the time of this article (early 20th century):

The Nestorians of Malabar, after kneading the flour with leaven, are accustomed to work in some of the leaven left from the preceding baking. They believe that this practice dates from the earliest Christian times and that it preserves the leaven brought to Syria by Saints Thomas and Thaddeus, for, according to another Nestorian tradition, the Apostles, prior to their separation celebrated the Liturgy in common and each carried away a portion of the bread then consecrated.

We can’t be sure if it’s historically true, but if the Saint Thomas Christians of India did make the Eucharistic bread via the starter dough method, then the leaven could very well be of darn ancient origins.

Another source of leavening was flour mixed with grape must (freshly-pressed grape juice that still contained the solid parts of the grape). Some beer-drinking peoples like the Gauls and Iberians (in modern France and Spain, respectively), meanwhile, used beer foam as leavening.

Origines Ecclesiasticæ: The Antiquities of the Christian Church by Joseph Bingham

Fourthly, we are to observe upon this head, That so long as the people continued to make oblations of bread and wine, the elements for the use of the eucharist were usually taken out of them ; and by consequence, so long the bread was that common leavened bread, which they used upon other occasions ; and the use of wafers and unleavened bread was not known in the church till the eleventh or twelfth centuries, when the oblations of common bread began to be left off by the people. This will seem a great paradox to all who look no further than the schoolmen, and only read their disputes with the Greeks about leavened and unleavened bread, which are fierce enough on both sides, and have little of truth on either : as commonly such disputes evaporate into smoke, and end in bitter and false reproaches ; the Greeks terming the Latins Azymites, for consecrating in azymis, that is, unleavened bread ; and the Latins, on the other hand, charging the Greeks with deviating from the example of Christ, and the practice of the ancient church. I will not enter into the detail of the arguments on both sides, which belongs not to this place ; but only acquaint the reader, that now the most wise and learned men in the Roman church, who have more exactly scanned and examined this matter, think fit to desert the schoolmen, and maintain, that the whole primitive church, and the Roman church herself for many ages, never consecrated the eucharist in any other but common and leavened bread.​

New Commentary on the Code of Canon Law by John P. Beal, James A. Coriden and Thomas J. Green

The requirement of unleavened bread is for liceity. In the early centuries, both Eastern and Western Churches used leavened bread for the Eucharist, but in the eighth and ninth centuries the use of unleavened bread became the general custom in the West. In keeping with the scope of the Code, the canon properly addresses only the practice of the Latin Rite.​

Primary Readings on the Eucharist

A practical reason for abolishing intinctio was the fear of spillage. The presence of Christ required extreme care that not a drop should be lost. This almost scrupulous piety was also applied to the host. Around the year 800 came the first prescriptions calling for the use of unleavened bread. This type of bread, which does not produce crumbs, came into general use from the eleventh century. The introduction of seperate hosts did away with the breaking of the bread.The hosts were prepared with the utmost care: the monks of Cluny washed themselves and combed their hair beforehand and picked out the wheat grains one by one and washed them. Even the millstone was cleansed. The monks were careful that neither their saliva nor their breath came into contact with the hosts.
Once consecrated, the bread belonged in sacred vessels. In Carolinian times the custom arose of consecrating such vessels, a gesture again exclusively reserved to the priest. The first sacred formulae for this type of ritual are to be found in the Gallic sacramentaries. The Missal Francorum, for instance, contains prayers for the consecration of the paten (This was originally a large tray used for distributing the leavened bread. When unleavened bread was introduced in the 8th-9th century and small hosts became more common, the tray lost its original shape and turned into a small flat dish on which the celebrant’s host was placed), the chalice, and the chrismale, the latter called allegorically by the Missale “a new tomb for the body of Christ.”

Fr. Joseph Jungman – in his book The Mass of the Roman Rite – states that:

"In the West, various ordinances appeared from the ninth century on, all demanding the exclusive use of unleavened bread for the Eucharist. A growing solicitude for the Blessed Sacrament and a desire to employ only the best and whitest bread, along with various scriptural considerations – all favored this development.

“Still, the new custom did not come into exclusive vogue until the middle of the eleventh century. Particularly in Rome it was not universally accepted till after the general infiltration of various usages from the North” [Joseph Jungman, The Mass of the Roman Rite, volume II, pages 33-34]​

Fr. Jungman goes on to say that,

“. . . the opinion put forward by J. Mabillon, Dissertatio de pane eucharistia, in his answer to the Jesuit J. Sirmond, Disquisitio de azymo, namely, that in the West it was always the practice to use only unleavened bread, is no longer tenable” [Jungman, The Mass of the Roman Rite, volume II, page 33]​

Now, the fact that the West changed its practice and began using unleavened bread in the 8th and 9th century – instead of the traditional leavened bread – is confirmed by the research of Fr. William O’Shea, who noted that along with various other innovative practices from Northern Europe, the use of unleavened bread began to infiltrate into the Roman liturgy at the end of the first millennium, because as he put it,

“The Eucharistic bread has been unleavened in the Latin rite since the 8th century – that is, it is prepared simply from flour and water, without the addition of leaven or yeast. . . . in the first millennium of the Church’s history, both in East and West, the bread normally used for the Eucharist was ordinary ‘daily bread,’ that is, leavened bread, and the Eastern Church uses it still today; for the most part, they strictly forbid the use of unleavened bread. The Latin Church, by contrast, has not considered this question very important.” [Dr. Johannes H. Emminghaus, The Eucharist: Essence, Form, Celebration, page 162]

On the one hand I have all these scholars who are basically sourcing their information from what is obviously a relatively recent speculation, the original source I have yet to identify, but I believe it to be over-simplified. There is the commonality of 8th or 9th Century for instance. The earliest mention is Alcuin, who just so happened to be born in the 8th Century and died in the 9th Century. Do we have a council which stated a canon?

Combined with the fact that it only became an East West issue 2 or 3 Centuries later, and from what I have read it is largely the East who promoted the dispute. (Thats just the impression I have got).

On the other hand, I see the origin being the Seder Jewish Passover. I also see the early Christian Church being eschatological (time to go), combined with persecution (time to go). We should also be eschatological in our own lives, too. Each eucharistic celebration could be our last. So there is the sense in the early Church of impending exit, or exodus surrounded by unleavened bread.

I should also mention the Greek. The word for bread in Greek is artos. This word does not imply leavened nor unleavened. There is another word azumos, which is used specifically to imply not leavened. However while the word has been translated “unleavened bread” this is not the meaning of the word. It just simply means unleavened. The feast of unleavened bread which the Jews celebrated was not specifically the feast of unleavened bread it was the feast of the unleavened. Unleavened everything. Just try and buy yeast in Israel during the feast of unleavened.

With that understanding, I have heard the argument that if it were meant to be unleavened bread the Greek would state azumos. But instead the Greek has artos. This is fairly much an invalid argument. It was not simply something unleavened, it was specifically bread. And in the context of the Jewish Passover the bread would have been azumos without being stated for the obvious historical reasons.

I have yet to see any sources demonstrating the Church in the West using anything but leavened bread in the first 8 centuries other than the repeated claim that “we’ve always used unleavened bread”.
I have come across multiple references from the change in the size of the paten used to carry the bread, to changes in the liturgy (mass, for you guys) due to no longer communing from the one loaf. The ancient sources all demonstrate the use of leavened bread in the West. It is not speculation.

The point can be granted that leavened bread was used in the West.

So we changed practice. No big deal.

Tell that to the Catholics who swear that Latins have ALWAYS used unleavened bread.
Also, the use of leavened bread in the East has an underlying theology associated with it. A change in the bread indicates a change in the theology, so it is kind of a big deal.

And all I ask is for you to demonstrate all of them, and if I hear another modern author, I will assume a mistranslation between what I have asked of you and what you have respond.

Are you referring to the resurrection, a raising from the dead, transferred to the rising of the bread?

If you are I find that a valid relationship, however there could be no resurrection, unless first there was a flat-line.

If the Eucharist could only exist after the resurrection, then the Eucharist could not exist in the upper-room where it was instituted, it would simply be a rehearsal, and Jesus Christ could easily have instituted a post-resurrectional Eucharist with leavened bread during the 40 days.

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