Acts 5:39 New English Translation

³⁹but if^[a] it is from God, you will not be able to stop them, or you may even be found^[b] fighting against God.” He convinced them,^[c]

Acts 5:39 tn This is expressed in a first class condition, in contrast to the condition in v. 38b, which is third class. As such, v. 39 is rhetorically presented as the more likely option.
Acts 5:39 tn According to L&N 39.32, the verb εὑρεθῆτε (heurethēte, an aorist passive subjunctive) may also be translated “find yourselves”—“lest you find yourselves fighting against God.” The Jewish leader Gamaliel is shown contemplating the other possible alternative about what is occurring.
Acts 5:39 tn Grk “They were convinced by him.” This passive construction was converted to an active one (“He convinced them”) in keeping with contemporary English style. The phrase “He convinced them” is traditionally placed in Acts 5:40 by most English translations; the standard Greek critical text (represented by NA²⁸ and UBS⁵) places it at the end of v. 39.

New English Translation (NET)