First Aoristsnapshot of the past

The Greek name ἀ-όριστος means "un-bounded" or "un-defined." What the aorist really carries is perfective aspect — action portrayed AS A SINGLE COMPLETED WHOLE, a snapshot rather than a movie. The first aorist locates that perfective action in past time. So the first aorist carries two things at once: PAST TIME + PERFECTIVE ASPECT.

Compare the two past-tense aspects:

• Imperfect (Lesson 14) — past time + imperfective aspect ("he was loosing / kept loosing"). The MOVIE view.
• First aorist (this lesson) — past time + perfective aspect ("he loosed"). The SNAPSHOT view.

The first aorist uses the present stem PLUS a tell-tale -σα tense formative. The aorist is the most common past tense in the NT and the default for narrative. When Mark says "Jesus came," "Jesus said," "Jesus did this," he overwhelmingly uses aorists. The imperfect is a deliberate departure for special effect.

Greek has TWO ways of forming the aorist; each verb uses one or the other (never both):

1. First (sigmatic) aorist — uses the present stem PLUS the -σα tense formative. About 90% of NT verbs. Regular and predictable. λύω → ἔλυσα; πιστεύω → ἐπίστευσα; ἀκούω → ἤκουσα. This lesson.
2. Second (thematic) aorist — uses a CHANGED stem with imperfect-like endings. About 10% of NT verbs but several high-frequency: βάλλω → ἔβαλον; ἔρχομαι → ἦλθον; λέγω → εἶπον; λαμβάνω → ἔλαβον. Lesson 16.

Both aorists carry the SAME aspect (perfective / snapshot) and the SAME time (past). They differ only in HOW the aorist stem is formed. The lexicon tells you which: the verb's third principal part (PP 3) is its aorist 1 sg form, and you can see at a glance whether it has a -σα (first aorist) or a stem-change with -ον endings (second aorist).

The -σα tense formative is the diagnostic for the first aorist. It sits between the verb stem and the personal endings. The full recipe:

AUGMENT + verb stem + -σα + secondary ending

Applied to λύω: ἐ- (augment) + λυ- (stem) + -σα (formative) = ἔλυσα ("I loosed"). When the verb stem ends in a stop consonant (π β φ / κ γ χ / τ δ θ ζ), the σ contracts with that stop — labial+σ → ψ, velar+σ → ξ, dental drops before σ. See Part 4 below for the full rules.

First aorist active endings: -σα, -σας, -σε(ν), -σαμεν, -σατε, -σαν. First aorist middle endings: -σάμην, -σω, -σατο, -σάμεθα, -σασθε, -σαντο. Note: 1 sg active is -α (not -ον like the imperfect's). 3 pl active is -αν (not -ον). This is the main parsing difference from the imperfect.

Any single first-aorist form can validly translate three ways. ἔλυσε(ν) can be:

1. Simple past — "he loosed." (Default; safest for ~95% of contexts.)
2. Undefined past — "he loosed [at some point]." (For summary or vague contexts.)
3. Gnomic / proverbial — "he looses [as a general truth]." (Rare; for proverbs and timeless statements like ἐξηράνθη ὁ χόρτος "the grass withers," 1 Pet 1:24.)

The Greek form gives you no help in choosing; you decide by reading context. Default to simple past unless the context cues otherwise.

⚠ Perfective aspect ≠ "instantaneous." The aorist makes no claim about duration. ἐβασίλευσε can mean "he reigned" (for forty years) or "he became king" (in a moment). What the aorist asserts is the speaker's choice to view the action as a whole, not as unfolding. Older grammars sometimes called this "punctiliar"; the pedagogical name "snapshot" captures it best.

Every Greek verb has six principal parts (PPs); the THIRD PP is the aorist active indicative 1 sg. Memorize each verb together with its PP 3 — ἔλυσα for λύω, ἔγραψα for γράφω, ἐπίστευσα for πιστεύω, ἤκουσα for ἀκούω. Without PP 3 you cannot form the aorist; with it, the whole paradigm follows by rule.

The six principal parts of a Greek verb (using λύω as the model):

1. λύω (PP 1) — pres act ind 1 sg
2. λύσω (PP 2) — fut act ind 1 sg (Lesson 18)
3. ἔλυσα (PP 3) — aor act ind 1 sg (THIS LESSON)
4. λέλυκα (PP 4) — perf act ind 1 sg (Lesson 19)
5. λέλυμαι (PP 5) — perf mid/pass ind 1 sg (Lesson 20)
6. ἐλύθην (PP 6) — aor pass ind 1 sg (Lesson 17)

From Lesson 15 onward, lexical entries in this course will list verbs with their PP 3 alongside the lexical (PP 1) form.

The first aorist uses secondary endings (just like the imperfect), but the -σα formative absorbs into them, producing the surface chain shown below. Strictly, the raw secondary suffixes are -, -ς, -, -μεν, -τε, -ν attached to the stem-vowel-bearing tense formative -σα-.

Add the augment ἐ- (syllabic, since λυ- begins with a consonant). Attach the stem λυ-. Insert the tense formative -σα-. Then add the secondary ending. The 3 sg is the ★ SPECIAL case — the α of -σα drops before the 3 sg -ε(ν).

The surface paradigm with accents and translations. This is what you memorize.

The middle paradigm follows the same recipe with the middle secondary endings. The only special cell is the 2 sg ἐλύσω, where historical -σασο drops its intervocalic σ and the resulting α + ο contracts to -σω. (Compare the imperfect 2 sg M/P -ου from -εσο → -εο → -ου — same σ-drop principle, different starting vowels, different contraction product.)

⚠ The aorist middle is DISTINCT from the aorist passive (which uses -θη, Lesson 17). The middle/passive ambiguity of the present and imperfect ENDS in the aorist. ἐλύσατο = aorist MIDDLE only; ἐλύθη = aorist PASSIVE.

The labial family (π β φ — lips) combines with σ to form ψ.

The velar family (κ γ χ — back of mouth) combines with σ to form ξ.

The dental family (τ δ θ, and ζ which behaves as a dental) DROPS before σ, leaving just σα visible.

Up to this point in the verb course, you've learned:

• Lessons 10–13 — the present-tense system: present active, contract verbs, middle/passive, and εἰμί. Five categories per verb (person, number, tense, voice, mood).
• Lesson 14 — the imperfect indicative: past action portrayed as ongoing or repeated. You met the augment (the ἐ- prefix that marks past time) and secondary endings.

Now we meet the first aorist. Like the imperfect, it's a past tense — so it has the augment and uses secondary endings. The new piece is its aspect: where the imperfect zooms in on the unfolding action ("she was teaching"), the aorist gives you a single snapshot ("she taught"). Mechanically, the aorist also adds a tense formative σα between the stem and the endings — a clear visual marker. So when you see a verb with both an augment and a σα, you're almost certainly looking at a first aorist.

Compare three ways to describe Jesus's teaching:

Present: διδάσκει "he teaches" — happening now, ongoing.

Imperfect: ἐδίδασκεν "he was teaching" / "kept teaching" — happening in the past, ongoing or repeated.

Aorist: ἐδίδαξεν "he taught" — happened in the past, end of story. No comment on duration.

The aorist is the default narrative past tense in the NT. When Mark says "Jesus said," "Jesus came," "Jesus did this," he overwhelmingly uses aorists. The imperfect is a deliberate choice against the aorist for special effect.

The pattern: augment + stem + σα + secondary endings.

For λύω: ἐ + λυ + σα → ἔλυσα ("I loosed")

The pattern is phonetic. Two consonants in a row (stop + σ) merge into a single double-letter (ψ, ξ) or simplify (dental + σ → σ alone). Latin ("scripsi" from "scribo") shows the same logic.

For verbs whose stems end in liquids (λ, μ, ν, ρ), the σ is dropped entirely and the previous vowel typically lengthens. These are often called liquid aorists:

1. Augment. Like the imperfect — ἐ- before consonants, vowel lengthening for vowel-initial stems.

2. σα or just α (in liquid aorists) before the personal ending. The aorist's tell.

3. Secondary endings. -ν, -ς, -ε(ν), -μεν, -τε, -ν (active) or -μην, -σο, -το, -μεθα, -σθε, -ντο (middle).