Prepositions and εἰμί

Prepositions

A preposition is a small word like 'in', 'from', or 'with' that introduces a phrase. In Greek, every preposition demands a particular case for the noun that follows it, and the case is part of the meaning. You never learn a preposition alone — you learn it together with its case.

Some prepositions take only one case: ἀπό + genitive ('from, away from'), ἐκ + genitive ('out of'), ἐν + dative ('in, on'), σύν + dative ('with'), εἰς + accusative ('into, to'). A helpful memory picture: genitive prepositions tend to express separation or source (from, out of), dative expresses rest (in, with), and accusative expresses motion (into).

Others take two cases with a real difference in meaning: διά + genitive is 'through', but διά + accusative is 'because of'; μετά + genitive is 'with', but μετά + accusative is 'after'; κατά + genitive is 'against', but κατά + accusative is 'according to'; ὑπό + genitive is 'by' (an agent), but ὑπό + accusative is 'under'. The case is not decoration — it changes the translation.

Before a word starting with a vowel, the final vowel of many prepositions drops off (elision): διά becomes δι᾽ in δι᾽ ἀποστόλου ('through an apostle'). Before a rough breathing, π and τ also change to φ and θ: μετά becomes μεθ᾽ in μεθ᾽ ἡμέραν ('after a day'). Recognize these altered spellings — they are the same prepositions you know.

• ἐν τῷ οἴκῳ — in the house (dative = location)
• εἰς τὸν οἶκον — into the house (accusative = motion)
• μετ᾽ ἀποστόλου — with an apostle (elision before a vowel)

εἰμί

The verb εἰμί ('I am') is the most common verb in Greek and, as in most languages, the most irregular. Its present forms — εἰμί, εἶ, ἐστί(ν), ἐσμέν, ἐστέ, εἰσί(ν) — do not look like the λύω pattern, so they must simply be memorized. You will see them so often that this happens quickly.

One grammar point matters for translation: εἰμί can connect a subject with a noun or adjective that describes it. In ὁ μαθητὴς προφήτης ἐστίν, 'the disciple is a prophet', both nouns are nominative. The describing noun is called a predicate nominative; it is not an accusative object. εἰμί can also mean 'exist' or tell where someone is, as in ὁ μαθητὴς ἐν τῷ οἴκῳ ἐστίν, 'the disciple is in the house'.

Most present forms of εἰμί are enclitic: they normally lean on the preceding word and lack their own written accent. Their spelling changes in some positions. ἐστί, ἐστι, and ἔστι can all be forms of the same verb; the optional note explains when accents appear.

• ὁ μαθητὴς προφήτης ἐστίν. — The disciple is a prophet (two nominatives).
• ἀγαθός ἐστιν ὁ λόγος. — The word is good (the adjective describes the subject).

Vocabulary (15)

ἀπό

(+gen) from, away from

ἐκ, ἐξ

(+gen) out of, from

ἐν

(+dat) in, on, among

σύν

(+dat) with, together with

εἰς

(+acc) into, to

διά, δι᾽

(+gen) through; (+acc) because of

μετά, μετ᾽, μεθ᾽

(+gen) with; (+acc) after

κατά, κατ᾽, καθ᾽

(+gen) against; (+acc) according to

περί

(+gen) concerning; (+acc) around

ὑπό, ὑπ᾽, ὑφ᾽

(+gen) by; (+acc) under

πρός

(+acc) to, toward, with

εἰμί

I am, exist

ἀλλά

but, rather

γάρ

for (postpositive)

ὡς

as, like, about