4. We told you before. In the short time that Paul and his companions were with the Thessalonians, they endeavored to prepare them for the inevitable trouble that lay ahead (see Acts 18:23). To begin with, these believers knew of the terrible flogging that Paul and Silas had received at Philippi (see on 1 Thess. 2:2). In their preaching, the missionaries had forewarned them of the coming persecution. Now Paul reminds them of his prediction and its painful fulfillment. The verity of the apostolic word must have confirmed the Thessalonians’ confidence in it ( on John 13:19), and have provided an effective incentive to steadfastness.
We should suffer tribulation. Or, “we are about to suffer tribulation.”