Voice is the property of the verb that indicates how the subject is related to the action (or state) expressed by the verb. In general, the voice of the verb may indicate that the subject is doing the action (active), receiving the action (passive), or both doing and receiving (at least the results of) the action (middle).
In general it can be said that in the active voice the subject performs, produces, or experiences the action or exists in the state expressed by the verb.
1. Simple Active
The subject performs or experiences the action. The verb may be transitive or intransitive. This is the normal or routine use, by far the most common.
Mark 4:2 He was teaching them many things in parables
2. Causative (Ergative) Active [cause]
The subject is not directly involved in the action, but may be said to be the ultimate source or cause of it. That cause may be volitional, but is not necessarily so. For the simple verb, sometimes the gloss cause to can be used before the verb and its object; in such cases it is sometimes best to convert the verb to a passive (e.g., he causes him to be baptized).
Matt 5:45 He causes his sun to rise on [both] evil and good [people], and he causes it to rain on [both] the righteous and unrighteous.
3. Stative Active
The subject exists in the state indicated by the verb. This kind of active includes both equative verbs (copulas) and verbs that are translated with an adjective in the predicate (e.g. "I am rich").
Luke 16:23 [the rich man] existing in a state of torment.
John 1:1 In the beginning was the Word.
4. Reflexive Active
The subject acts upon himself or herself. In such cases naturally the reflexive pronoun is employed as the direct object (e.g., eauton), while the corresponding reflexive middle omits the pronoun.
Mark 15:30 Save yourself!
1Tim 4:7 Train yourself toward godliness!
Defining the function of the middle voice is not an easy task because it encompasses a large and amorphous group of nuances. But in general, in the middle voice the subject performs or experiences the action expressed by the verb in such a way that emphasizes the subject's participation. It may be said that the subject acts with a vested interest. "The middle calls special attention to the subject ... the subject is acting in relation to himself somehow" (Roberson, 804).
The difference between the active and middle voice is one of emphasis. The active emphasizes the action of the verb; the middle emphasizes the actor [subject] of the verb. For many middle voices (especially the indirect middle), putting the subject in italics would communicate this emphasis.
1. Direct (Reflexive, Direct Reflexive) Middle
With the direct middle, the subject acts on himself or herself. the genius of the middle can most clearly be seen by this use. But because of its very subtlety, nonnative speakers tended to replace this with more familiar forms. In th eNT, the direct middle is quite rare, used almost exclusively with certain verbs whose leical nuance included a reflexive notion (such as putting on clothes), or in a set idiom that had become fixed in the language.
Matt 27:5 He hanged himself
2. Indirect (Indirect Reflexive, Benefactive, Intensive, Dynamic) Middle
The subject acts for (or sometimes by) himself or herself, or in his or her own interest. This is a common use of the middle in the NT; apart from the deponent middle, it is the most common. This usage is closest to the general definition of the middle suggested by many grammarians.
Acts 5:2 And he kept back [some] of the price [for himself]
Matt 27:24 Pilate washed his hands saying, "I am innocent of this man's blood."
3. Causative Middle
The subject has something done for or to himself or herself. As well, the subject may be the source behind an action done in his/her behalf. This usage, though rare, involves some exegetically important texts.
Luke 11:38 When the Pharisee saw this, he was amazed because [Jesus] did not first have himself washed before the meal.
4. Permissive Middle
The subject allows something to be done for or to himself or herself. This usage, though rare, involves some exegetically important texts.
Luke 2:4-5 Joseph went up from Galilee ... (5) to be enrolled with Mary.
Acts 22:16 Rise, have yourself baptized and allow your sins to be washed away.
5. Deponent Middle
A deponent middle verb is one that has no active form for a particular principal part in Hellenistic Greek, and one whose force in that principal part is evidently active. See Wallace for his list of true deponents.
In general it can be said that in the passive voice the subject is acted upon or receives the action expressed by the verb. No volition - nor even necessarily awareness of the action - is implied on the part of the subject. That is, the subject may or may not be aware, its volition may or may not be involved. But these things are not stressed when the passive is used.
[Wallace breaks his discussion of the passive voice into "Passive construction" (with and without expressed agency, and the passive with an accusative object) and three "Passive uses," two of which are listed below.]
1. Simple Passive
The most common use of the passive voice is to indicate that the subject receives the action. No implication is made about cognition, volition, or cause on the part of the subject. This usage occurs both with and without and expressed agent.
Mark 4:6 When the sun rose, it was scorched.
Acts 1:5 You will be baptized with the Holy Spirit.
2. Deponent Passive
A verb that has no active form may be active in meaning though passive in form.
Edition: Feb 10,2009