The Present For The Future
In a similar way the Present Indicative may be used to describe vividly a future event.
Mark 9:31; Ὁ υἱὸς τοῦ ἀνθρώπου παραδίδοται εἰς χεῖρας ἀνθρώπων, the Son of man is delivered into the hands of men. See also Matt. 26:18, ποιῶ; 27:63, ἐγείρομαι; Luke 3:9, ἐκκόπτεται.
REMARK. The term “Present for Future” is sometimes objected to, but, without good reason. The arguments of Buttmann, pp. 203f., and Winer, WT. pp. 265 ff.; WM. pp. 331 ff., are valid only against the theory of an arbitrary interchange of tenses. It is indeed not to be supposed that Greek writers confused the Present and the Future tenses, or used them indiscriminately. But that the form which customarily denoted an act in progress at the time of speaking was sometimes, for the sake of vividness, used with reference to a fact still in the future, is recognized by all grammarians. The whole force of the idiom is derived from the unusualness of the tense employed.
The Present form ἥκω means I have come (John 2:4; 4:47; etc.). Similarly πάρειμι (I am present) sometimes means I have arrived (Acts 17:6; etc.). This, however, is not a Present for the Perfect of the same verb, but a Present equivalent to the Perfect of another verb. The use of ἀκούω meaning I am informed (cf. similar use of English hear, see, learn) is more nearly a proper Present for Perfect (1 Cor. 11:18; 2 Thess. 3:11). Such use of the Present belongs to a very few verbs.