But having suffered before (alla propathontes). Strong adversative alla, antithesis to kenē. Appeal to his personal experiences in Thessalonica known to them (as ye know, kathōs oidate). Second aorist active participle of propaschō, old compound verb, but here alone in the N.T. The force of prȯ (before) is carried over to the next verb. The participle may be regarded as temporal (Ellicott) or concessive (Moffatt).
And been shamefully entreated in Philippi (kai hubristhentes en Philippois). First aorist passive participle of hubrizō, old verb, to treat insolently. “More than the bodily suffering it was the personal indignity that had been offered to him as a Roman citizen” (Milligan), for which account see notes on Acts 16:16-40, an interesting example of how Acts and the Epistles throw light on each other. Luke tells how Paul resented the treatment accorded to him as a Roman citizen and here Paul shows that the memory still rankled in his bosom.
We waxed bold in our God (eparrēsiasametha en tōi theōi hēmōn). Ingressive first aorist middle of parrēsiazomai, old deponent verb from parrēsia (full story, pan-, rēsia). In his reply to Festus (Act 26:26) Paul uses parrēsiazomenos lalō, being bold I speak, while here he has we waxed bold to speak (eparrēsiasametha lalēsai). The insult in Philippi did not close Paul’s mouth, but had precisely the opposite effect “in our God.” It was not wild fanaticism, but determined courage and confidence in God that spurred Paul to still greater boldness in Thessalonica, unto you (pros humās), be the consequences what they might, the gospel of God in much conflict, (to euaggelion tou theou en pollōi agōni). This figure of the athletic games (agōn) may refer to outward conflict like Phi 1:30 or inward anxiety (Col 2:1). He had both in Thessalonica.