Καὶ ἐμαρτύρησεν Ἰωάννης λέγων
Be able to identify and explain all these parts of εμαρτυρησεν ε μαρτυρ σε ν
ἸωάννηςWhat case is Ιωαννης?
ὅτι τεθέαμαι τὸ πνεῦμα καταβαῖνον ὡς περιστερὰν ἐξ οὐρανοῦ καὶ ἔμεινεν ἐπ᾽ αὐτόν.
οτι often introduces direct discourse in which case it is translated with quotation marks (know the difference between direct and indirect discourse).
καταβαινον is a participle modifying πνευμα. It is anarthrous but still adjectival. Here it is an attributive participle which means you will translate it with a relative clause. Here is the evolution (BBG 27.3):
καταβαιν- compound verb stem
καταβαινo add the connecting vowel
καταβαινοντ add the participle morpheme
καταβαινoν the τ drops off (as per noun rule #8)
καταβαινον add the case ending (there isn’t one in this case)
κἀγὼ οὐκ ᾔδειν αὐτόν, ἀλλ᾽ ὁ πέμψας με βαπτίζειν ἐν ὕδατι ἐκεῖνός μοι εἶπεν·
βαπτίζεινWhat usage of the infinitive do we see in βαπτιζειν?
With what (or in what) were they baptized? ἐν ὕδατι υδατι is dative; cf. MBG 199; n-3c(6b).
ἐφ᾽ ὃν ἂν ἴδῃς τὸ πνεῦμα καταβαῖνον καὶ μένον ἐπ᾽ αὐτόν, οὗτός ἐστιν ὁ βαπτίζων ἐν πνεύματι ἁγίῳ.
εφ is from επι. Why the changed spelling?
The αν causes our translation of ον to change from “whom” to “whomever”.
The lexical form is οραω. Why no augment? What would the verb ending be if it were not subjunctive? You should be able to determine the person, number, and voice from the verb ending. What is the subject? object?
καταβαινον and μενον
Note that εστιν is a linking verb. The entire phrase that follows is the PN. βαπτιζων is articular and a substantival participle. Since it is a substantive, we expect it to be performing one of the noun functions. The evolution of καταβαινον is given above; here is μενον (BBG 27.3):
κἀγὼ ἑώρακα καὶ μεμαρτύρηκα ὅτι οὗτός ἐστιν ὁ υἱὸς τοῦ θεοῦ.
ἑώρακα is from ὁράω
μεμαρτυρηκα is much more regular.What is the DO of εωρακα and μεμαρτυρηκα?