But certain Jews from Asia (tines de apo tēs Alias Ioudaioi). No verb appears in the Greek for these words. Perhaps he meant to say that “certain Jews from Asia charged me with doing these things.” Instead of saying that, Paul stops to explain that they are not here, a thoroughly Pauline anacoluthon (2Co 7:5) as in Act 26:9. “The passage as it stands is instinct with life, and seems to exhibit the abruptness so characteristic of the Pauline Epistles” (Page).
Who ought to have been here before thee (hous edei epi sou pareinai). This use of epi with genitive of the person is common. The imperfect indicative with verbs of necessity and obligation to express failure to live up to it is common in Greek (Robertson, Grammar, pp. 919-21). “The accusers who were present had not witnessed the alleged offence: those who could have given evidence at first-hand were not present” (Furneaux). There was no case in a Roman court. These Asiatic Jews are never heard of after the riot, though they almost succeeded in killing Paul then.
If they had aught against me (ei tōi echoien pros eme). A condition of the fourth class or undetermined with less likelihood of being determined (ei with the optative, Robertson, Grammar, p. 1021). This is a “mixed condition” (op.cit., p. 1022) with a conclusion of the second class.