ἐπιούσιος

There is one word in the New Testament that should not exist.

It appears twice in the entire New Testament corpus. Once in Matthew, once in Luke. Both times in exactly the same context — the Fourth Petition of the Lord’s Prayer:

“Give us this day our daily bread.” (Matthew 6:11, ESV)

“Give us each day our daily bread.” (Luke 11:3, ESV)

The Greek word translated “daily” is epiousios. It appears in those two verses and nowhere else in the New Testament. More remarkably: epiousios appears nowhere else in extant Greek literature before the New Testament. The word does not show up in classical Greek philosophy, in Hellenistic Greek popular writing, in the Septuagint translation of the Old Testament, or in any of the Greek papyri scholars have recovered from the ancient world — with one fragmentary and contested possible exception, an Egyptian housekeeping account that may date from a period when Christian usage of the word had already spread.

In a sense, the word does not exist outside the Lord’s Prayer. It appears to have been coined, almost certainly, for this specific petition — either by the evangelists when they rendered Jesus’s Aramaic teaching into Greek, or by Greek-speaking Christians very close to the apostolic generation who needed a new compound to capture something Jesus had said that no existing Greek word quite did. Origen, writing in the third century, noted that the word is “not used by any Greek writer” and observed its strangeness directly.

This is the chapter on epiousios. It closes Part V on the Spirit and the Christian life, and it is the most lexically peculiar chapter in this book. The word is mysterious. The translation is contested. The interpretation has divided commentators for nearly two thousand years. And yet — and this is what makes the chapter worth writing — the basic substance the petition asks for is one of the most beloved and most prayed-for gifts in the Christian life: the daily provision that comes from God through the ordinary structures of His creation, sustaining His people through their callings until He returns.

The Word

ἐπιούσιος (epiousios), pronounced eh-pee-OO-see-os. An adjective. The etymology is contested, and the lexical mystery has occupied commentators since the patristic period. There are three main proposals for how the word was formed, and each yields a different translation of “daily bread.”

The word appears to be a compound. The first element is clearly the preposition epi (ἐπί, “on, upon, over, at, for”). The second element is what is disputed. The three main proposals divide the scholarly conversation:

Proposal one: epi + ousia (οὐσία, “being, substance, essence”). This would yield “supersubstantial” or “essential” — the bread that goes beyond mere physical sustenance. Jerome rendered the Matthew occurrence with the Latin neologism supersubstantialem. This is the basis of the traditional Roman Catholic Eucharistic reading: the bread asked for is the bread of the Supper, the bread that is the body of Christ, the bread that surpasses ordinary food. The lexical objection: the compound ousia + epi would normally drop the iota of epi, but epiousios retains it. The construction is unusual.

Proposal two: epi + a form of ienai (ἰέναι, “to come”) or eimi (εἰμί, “to be”) yielding the participle epiousa (ἐπιοῦσα, “the coming”). The Greek for “the coming day” is hē epiousa hēmera. So epiousios could mean “for the coming day” — that is, “for tomorrow.” This is the most defensible etymologically and the most favored by modern scholarship. It is also the reading that the Aramaic substratum behind the prayer may support — Jerome reported in his commentary on Matthew that the Gospel of the Hebrews (a Jewish-Christian gospel he had access to) rendered the Aramaic with a word meaning “of tomorrow.”

Proposal three: epi + the participle ousan (οὖσαν, “being, present”) from eimi (to be). Epi tēn ousan hēmeran would mean “for the day that is” — that is, “for the present day,” “for today.” This yields “daily” in the standard English sense and aligns with the traditional Greek-to-Latin-to-English chain that gave us cotidianum and “daily.”

The Vulgate split is striking:

• Matthew 6:11: panem nostrum supersubstantialem (our supersubstantial bread).
• Luke 11:3: panem nostrum cotidianum (our daily bread).

Same Greek word, different Latin translations. Jerome was clearly wrestling with the difficulty, and his solution was to give one rendering in Matthew (favoring Proposal 1) and another in Luke (favoring Proposal 3). The split persisted in Latin Christianity for centuries, with theological consequences for how the petition was read.

Modern English translations have generally settled on “daily,” following Proposal 3 or a soft form of Proposal 2 (since “daily” can cover both “for today” and “for tomorrow” depending on context). The Greek Orthodox Church has historically read epiousios in line with Proposal 2 (for the coming day, with eschatological dimensions). The Catechism of the Catholic Church (1992) acknowledges multiple readings while preserving the Eucharistic dimension Jerome’s Latin established.

The Hawara papyrus, discovered in Egypt and dating from approximately the fifth century AD, contains what some scholars have identified as the word epiousios in a fragmentary housekeeping account. If this attestation is genuine and represents non-Christian secular usage, it would support Proposal 3 (epiousios as the daily portion or ration of a household servant). But the dating is late, the document is fragmentary, the reading is contested, and Christian usage of the word may well have spread by the fifth century — so the papyrus does not settle the question.

The honest summary: the word is unique, its etymology is disputed, and the major translation traditions have made different choices. The good news is that the basic substance of the petition is clear enough regardless of which etymological proposal is correct.

Range of Meaning

Given the lexical mystery, the range of epiousios is constructed from the three proposals rather than from a normal lexicographical survey of attested usage:

1. Supersubstantial — the bread that surpasses mere physical sustenance. Proposal 1; basis of the Catholic Eucharistic reading.
2. For the coming day / for tomorrow — bread that sustains into the next day, with possible eschatological dimensions (the bread of the coming kingdom). Proposal 2; favored by modern scholarship and by Eastern Orthodox tradition.
3. Daily / for the present day — the bread for each day’s needs. Proposal 3; basis of the traditional English “daily.”

The three readings are not mutually exclusive in their pastoral application. The petition can be heard as asking for today’s bread (Proposal 3), for tomorrow’s bread (Proposal 2), and for the bread that surpasses ordinary food including the Lord’s Supper (Proposal 1) — at the same time, in different dimensions, all under one Greek word that has resisted neat definition for two thousand years.

Where You’ll Meet It

The word appears only in the two parallel versions of the Lord’s Prayer.

“Pray then like this: ‘Our Father in heaven, hallowed be your name. Your kingdom come, your will be done, on earth as it is in heaven. Give us this day our daily bread, and forgive us our debts, as we also have forgiven our debtors…’” (Matthew 6:9–12, ESV)

Matthew’s version, embedded in the Sermon on the Mount. The Fourth Petition stands between the third (your will be done on earth) and the fifth (forgive us our debts). The structural placement matters: after asking for God’s name, kingdom, and will, the prayer turns to the petitioner’s own needs — and the first need named is bread. The prayer assumes dependence; the petition expresses it; the bread is the daily expression of God’s faithfulness to His children.

“He said to them, ‘When you pray, say: “Father, hallowed be your name. Your kingdom come. Give us each day our daily bread, and forgive us our sins, for we ourselves forgive everyone who is indebted to us. And lead us not into temptation.”’” (Luke 11:2–4, ESV)

Luke’s version, given in response to a disciple’s request: “Lord, teach us to pray, as John taught his disciples.” Luke’s form is shorter than Matthew’s, and the present-tense verb “give” (didou in Luke, versus the aorist dos in Matthew) emphasizes the ongoing, continuous nature of the asking. “Keep on giving us each day our daily bread.” Both versions name the same word — epiousios — and both name the same petition. The slight variations in form do not change the substance.

These two occurrences are the entire New Testament data. Two verses. Same prayer. Same word. The chapter could be the shortest in the book on lexical grounds — but the pastoral substance the petition opens up has occupied the church for two thousand years.