37 Grk “in which [activity].” Due to the length and complexity of the Greek sentence, a new sentence was started at the beginning of v. 12 in the translation. The referent of the relative pronoun (“which”) was specified as “this very thing” for clarity.
38 Grk “going.” The participle πορευόμενος (poreuomenos) has been taken temporally.
39 L&N 37.40 ἐπιτροπή states, “the full authority to carry out an assignment or commission—‘authority, complete power.’ πορευόμενος εἰς τὴν Δαμασκὸν μετʼ ἐξουσίας καὶ ἐπιτροπῆς τῶν ἀρχιερέων ‘going to Damascus with authority and complete power from the high priests’ Ac 26:12. In Ac 26:12 the combination of ἐξουσία and ἐπιτροπή serves to reinforce the sense of complete authority.”

In other versions

“In this connection I journeyed to Damascus with the authority and commission of the chief priests.

“On one of these journeys I was going to Damascus with the authority and commission of the chief priests.

“I was traveling to Damascus under these circumstances with authority and a commission from the chief priests.

“One day I was on such a mission to Damascus, armed with the authority and commission of the leading priests.

In this activity I was traveling to Damascus with the authority and full power of the chief priests.

Whereupon as I went to Damascus with authority and commission from the chief priests,

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