Overview of Verbs

Greek verbs have five grammatical categories: mood, voice, tense, person, and number. That means that each instance of the verb that you encounter can be characterized by certain values of each category. Each verb can change across all five categories. 

Below, I give English examples to convey the rough idea of each mood, voice, etc. Those examples are very sketchy.

Note that the Greek verbs don't require the subject to be stated in the sentence. 

Mood describes the relationship between action and reality. There are 6 possible moods in Greek:

• Indicative mood -- Most common mood. Factual mood. Describes actions that took place. (The man opens the door)

• Subjunctive mood -- Potential mood. Describes wishes, possible outcomes, etc., i.e. actions that might take place. (The man would open the door...)

• Optative mood -- Very potential mood. Rarely appears in the New Testament. (no simple equivalent)

• Imperative mood -- Describes commands or requests, i.e. actions that should take place in the estimation of the speaker. (Open the door!)

• Infinitive mood -- Describes the idea or the concept of the action as such. Behaves like a noun. (to open the door)

• Participle -- An adjectival form of the action. Behaves like an adjective. (the opened door)

Voice describes the relationship between the subject of the sentence and the agent (the performer) and the target (the receiver) of the action. There are 3 voices in Greek:

• Active voice -- Most usual. The subject coincides with the agent. (The man opens the door)

• Middle voice -- No direct correspondence in English. The subject coincides with both the agent and the target. (The door opened itself)

• Passive voice -- The subject coincides with the target. (The door is opened)

Tense describes the relationship between action and time. It also describes the type of action. There are 6 tenses in Greek:

• Present -- Describes a continuous or simple present action. (The man opens the door or The man is opening the door)

• Future -- Describes a future action. (The man will open the door)

• Imperfect  -- Describes a continuous action in the past.  (The man was opening the door)

• Aorist -- Describes a simple action in the past. (The man opened the door)

• Perfect -- Describes a completed action. (The man has opened the door)

• Pluperfect -- Rarely used in the New Testament. Describes a completed action in the past. (The man had opened the door)

Person describes the relationship between the agent and the speaker. There are 3 persons in Greek:

• 1st person -- The agent is the speaker. (I open the door)

• 2nd person -- The agent is being spoken to. (You open the door)

• 3rd person -- The agent is neither the speaker nor the entity being spoken to. (The man opens the door)

Number describes what kind of entity the agent is. There are 2 numbers in Greek:

• Singular -- The agent is a singular entity. (The man opens the door)

• Plural -- The agent is a collection of entities. (The men open the door)

The Dictionary Form of the verb consists of 6 Principal Parts. For example λύω, λύσω, ἔλυσα, λέλυκα, λέλυμαι, ἐλύθην. Each of these principal parts is a first-person singular form of a certain tense-mood-voice combination. 

• The first principal part is Present Indicative Active

• The second principal part is Future Indicative Active

• The third principal part is Aorist Indicative Active

• The fourth principal part is Perfect Indicative Active

• The fifth principal part is Perfect Indicative Middle/Passive

• The first principal part is Aorist Indicative Passive

The short dictionary form is given by the first principal part.