kosta50: So, what? The meaning is the same. Take it up with publishers who disagree with you. And the KJV version is based on the corrupt Textus Receptus, which doesn't agree with any of the older reliable versions, namely: ἅγιοι ἔσεσθε ὅτι ἐγὼ ἅγιος εἰμι, a simple future: you will be holy because I am holy!
Since you had mentioned the second aorist I had assumed you were talking about vs. 15:
ἁλλὰ κατὰ τὸν καλέσαντα ὑμᾶς ἅγιον καὶ αὐτοὶ ἅτιοι ὲν πὰσῃ ἀναστροφῇ γενήθητεNor does the aorist and aorist imperative have the same meaning. Despite being called "aorist imperative", the designation aorist does not refer to the past tense but rather the indeterminate completion of the action. From two Greek grammars:
but, as he who called you is holy, be holy yourselves in every aspect of your conduct
1864. Imperative. —The imperative always implies future time. The tenses do not refer to differences of time, and denote only the stage of the action.The Septuagint version of Leviticus 19:2 reads like the reliable NT versions, namely ἅγιοι ἔσεσθε ὅτι ἐγὼ ἅγιος κύριος ὁ θεὸς ὑμῶν, a simple future "you will be[come]..." and not the way KJV fraud reads.
a. Present (continuance): τοὺς γονεῖς τίμα honour thy parents I.1.16, πάντα τά ληθῆ λέγε tell (go on and tell in detail) the whole truth L.1.18, τοὺς ἵππους ἐκείνοις δίδοτε offer the horses to them X.C.4.5.47.
b. Aorist (simple occurrence) : βλέψον πρὸς τὰ ὅρη look (cast a glance) toward the mountains X.A.4.1.20, εἰπέ state (in a word) P.A.24 d, ἡμῖν τοὺς ἵππους δότε give the horses to us X.C.4.5.47.
(Herbert Weir Smyth, Greek Grammar for Colleges, New York: American Book Company, 1920, p. 416)851. In the subjunctive, optative, imperative, and infinitive, the tenses do not of themselves designate time
The present in these modes denotes an action simply as continued : thus ποιεῖν to be doing (at any time).
The aorist denotes an action simply as brought to pass : ποιῆσαι to do (at any time).
(James Hadley, A Greek Grammar for Schools and Colleges, New York: American Book Company, 1912, p. 270.)
However, in Greek the future tense can be used to express command. Again from the two Greek grammars:
1917. Jussive Future. — The future may express a command, like the imperative; and, in the second person, may denote concession or permission. The negative is οὐ. The tone of the jussive future (which is post-Homeric) is generally familiar.Given that St. Peter is quoting Leviticus as his justification for his own command to be holy, this jussive future must be accepted. If you disagree with this interpretation, take it up with St. Peter.
ὠς οὖν ποιήσετε you will do thus P.Pr. 338a, ἀναγνώσεται τὸν νόμον — ἀναγίγνωσκε the clerk will read the law — read D.24.39, σπουδὴ ἔσται τῆς ὀδοῦ you will have to hurry on the march T.7.77, ὑμεῖς οὖν, ἐὰν σωφρονῆτε, οὐ τούτου ἀλλ᾽ὑμῶν φείσεσθε now, if you are wise, you will spare, not him, but yourselves X.H.2.3.34.
(Smyth, p. 428)844. The second person of the future is used as a softened form of command : πάντωσ δὲ τοῦτο δράσεις but this you shall do be all means (ArNub.1352).
(Handley, p. 268.)
I don't know why you would assume that given that 1 Pet 1:15 is in aorist, passive, imperative (γενήθητε), and 1 Pet 1:16 (in Textus Receptus) is in second aorist, middle (active), imperative (γένεσθε).
The difference between these two (in Textus Receptus only) is that 15 is in the passive voice, whereas 16 is in middle or active voice. In plain English it means that in 15 you are to (passively) receive holiness, while in 16 you are to (actively) achieve it!
However in older reliable versions of the Greek NT 1 Pet 1:16 is in future, no voice, indicative—something that will occur as a matter of fact. It is most definitely not a commandment (imperative) but logically follows verse 15.
Obviously Textus Receptus leads to a serious misunderstanding—and error. In the older, reliable, Greek texts, verses 15-16 speak of passive holiness that will be received by those who are God's people.
The corrupt Textus Receptus first states they will receive holiness passively, then it commands them to receive it actively!
Given that St. Peter is quoting Leviticus as his justification for his own command to be holy, this jussive future must be accepted.
The author of 1 Peter is issuing no such imperative! He is merely stating that God's people will (future, indicative) become holy through Him. :)
It's commendable but not enough to know Greek; it's equally important to have a reliable version of it. Otherwise you might see "jussive future" where there isn't one, and the whole message will lead into heresy.