Acts 1:23-26: two verbs for 'I call'

Ἰωσὴφ τὸν καλούμενον Βαρσαβᾶν, . . . . . Joseph the one called Barsabas

ὃς ἐπεκλήθη Ἰοῦστος . . . . who was called Justus

Καλούμενον is the masculine singular accusative form of the present middle/passive participle for the verb καλέω, 'I call, I name'.  

It is masculine and singular because it refers to the Ἰωσήφ / Βαρσαβᾶν.

It is accusative because Ἰωσήφ and Βαρσαβᾶν are both accusative (although you can't tell this with the indeclinable Ἰωσήφ), and they are accusative as the direct objects of ἔστησαν, 'they put forward'.

So Ἰωσήφ is called Βαρσαβᾶν.  Why do we also have the form ἐπεκλήθη, followed by Ἰοῦστος?

Ἐπεκλήθη is 3-S, aorist passive indicative of ἐπικαλέω, which is καλέω with ἐπί as a prepositional prefix - 'I call, I call upon'.

This formula for introducing an additional name via ἐπικαλέω is used several times in Acts:

name . . . . (form of) ἐπικαλέω . . . . another name

For example:

καὶ μετάπεμψαι Σίμωνά τινα ὃς ἐπικαλεῖται Πέτρος  (Acts 10:5)

τὴν οἰκίαν τῆς Μαρίας τῆς μητρὸς Ἰωάννου τοῦ ἐπικαλουμένου Μάρκου  (Acts 12:12)

συνπαραλαβόντες Ἰωάννην τὸν ἐπικληθέντα Μάρκον  (Acts 12:25)

I don't know why the individual in Acts 1:23 has three names.  Some translations refer to Ἰοῦστος as a surname.  

Επικαλέω is also commonly used in the sense of 'I call upon', or 'I appeal to'.  So for example:

ἠναγκάσθην ἐπικαλέσασθαι Καίσαρα . . . . I was forced to appeal to Caesar  (Acts 28:19)

Πᾶς γὰρ ὃς ἂν ἐπικαλέσηται τὸ ὄνομα Κυρίου σωθήσεται . . . . everyone who calls on the name of the Lord will be saved (Romans 10:13)

μετὰ τῶν ἐπικαλουμένων τὸν Κύριον ἐκ καθαρᾶς καρδίας . . . . along with those who call upon the Lord out of a pure heart (2 Timothy 2:22)

Τwo-thirds of the uses of ἐπικαλέω in the New Testament (20/30) are in Acts.

Next time: the adjective ἴδιος, ἰδία, ἴδιον