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During the latter half of the nineteenth century and into the latter half of the twentieth century, general linguists, Greek philologists, and New Testament grammarians have been wrestling with new theories to understand the Greek verbal system; some have been more successful than others. K. L. McKay has been instrumental for challenging New Testament scholars in the latter half of the twentieth century. At the end of the 1980’s two scholars working concurrently and unaware of each other’s research in the area of verbal aspect published two seminal volumes on the subject, Buist Fanning and Stanley Porter. The latter building on McKay’s system but grounded with much more linguistic theoretical rigor.
Verbal aspect theory emphasizes the distinction of form and function; semantics and pragmatics; spatial quality and temporal reference; aspect (i.e. author’s subjective portrayal of the action) and Aktionsart (i.e. objective “kind of action”). Traditionally, grammarians confused the latter elements with the former. For example, it was (and still is common among many New Testament interpreters) thought that the verb tense grammaticalized (or encoded) time. But verbal aspect argues that time is not an inherent (semantic) value of the morphological tense-form—only the lexeme and context can gives us clues to the temporal reference. And take for example Aktionsart (German for “kind of action). It was thought that the aorist encoded the kind of action, which is commonly thought of as “punctiliar”—happening at a point in time; further, it was understood that the aorist tense was “past” time. Instances that did not fit that function were relegated to “exceptions.” Verbal aspect, however, rejects that the aorist encodes these semantic values. The aorist is an undefined notion; the author chooses this tense-form to simply state the action as a whole or summary. It could be punctiliar, but the verb tense-form itself cannot tell us that; only the lexeme and context can reveal this to us. In addition, the aorist is not a “past” tense; even though it is found in past tense contexts most of the time; this is because the aspect of the verb is attracted to these contexts—what linguists call a pragmatic implicature. Aspect is that value of the verb system which an author chooses to portray or represent an action. Porter defines aspect as such:
a morphologically-based semantic category which grammaticalizes the author/speaker’s reasoned subjective choice of conception of a process—provides a suggestive and workable linguistic model for explaining the range of uses of the tense forms in Greek.
Porter recognizes three aspects in the Greek system: Perfective (Aorist), Imperfective (Present, Imperfect), and Stative (Perfect, Pluperfect). The perfective aspect views the action externally and is only concerned to view the action as a whole or as a simple event (not to be confused with punctiliar). The imperfective aspect views the action internally being concerned with portraying the action as it is unfolding or in progress (not to be confused with “continuous action,” which is an Aktionsart category). The stative aspect views the action as a state of affairs, a condition. These three aspects are not describing the kind of action. This kind of action, Aktionsart, is determined by the combination of lexeme and context. To summarize the differences between traditional grammar and verbal aspect:
Traditional view. Present tense is seen as a continuous action in present time; Aorist tense is punctiliar or undefined and in past time; Perfect tense viewed as a past action with results carried over to the author’s present time.
Verbal Aspect. Present tense is seen as unfolding or in progress without reference to temporality; Aorist tense as a complete whole or summary or simple event without reference to temporality; Perfect tense as a state of affairs without temporality.
 Rodney Decker, Temporal Deixis of the Greek Verb in the Gospel of Mark with Reference to Verbal Aspect. SBG 10, New York Peter Lang, 2001, 5-28.
 K. L. McKay. A New Syntax of the Verb in the New Testament Greek. New York: Peter Lang, 1994.
 Buist Fanning. Verbal Aspects in New Testament Greek. Oxford England: Clarendon, 1990; Porter.
 Stanley Porter, Verbal Aspect in the Greek of the New Testament, with Reference to Tense and Mood. SBG 1, New York: Peter Lang, 1993, xi.