To which Jews do 1 Thessalonians 2:14-16 refer?

Note, firstly, that Paul conceives of the Jews as a single group characterized by the various statements of verses 15-16a. Then observe that the group is first described as those who killed the Lord Jesus and the prophets. At this point, the focus would be on the Jews in Palestine but would include people over a span of centuries. Next, the statements about driving Paul out and preventing the gospel from being preached to the Gentiles would have to include Jews from outside of Palestine. Thus it appears that Paul has a fairly diverse group of Jewish people in mind. Clearly, though, he is not thinking of all Jewish people. There were Jewish believers in the churches of Judea who are obviously not included in the Jews whom Paul condemns in these verses; and in Romans 9:1 – 11:36 he affirms that there is a remnant of Jews saved by grace. Therefore, Paul is not condemning all Jews just because they are Jews. Rather, he is drawing on the biblical persecution tradition, which highlights the reality of persecution, even from those who claim to be the people of God. The Jews Paul has in mind are those who oppose and persecute God’s messengers, and who thereby hinder the proclamation of the gospel. They are worthy of condemnation (1 Thessalonians 2:16bc) because the effect of their actions is to expose other people to God’s condemnation by hindering their salvation (Matthew 23:13; Luke 11:52). Paul’s aim in making these negative statements about the Jews is to reassure the Thessalonian disciples that their experience is not unique and that their suffering is no indication that they were mistaken to put their faith in Jesus.

Lest Paul be suspected of anti-Semitism (which is hardly likely considering that he himself was a Jew), let us note that he is even more graphic in his condemnation of the Gentiles who persecuted the Thessalonian church (2 Thessalonians 1:7–10).