For all its doctrinal richness, this lengthy eschatological text was written primarily out of deep pastoral concern. As verses 1-2 make plain, a rumor was circulating among the Thessalonian house churches, to the effect that the Day of the Lord had come; that it was imminent. Since the rumor was troubling the brethren, distracting them from their spiritual mission and daily responsibilities, Paul addressed it pointedly. His message is clear: The Day of the Lord will not come until certain things happen first; until certain unmistakable signs appear on the historical horizon. So then: Until you see those signs, stand firm (2:15) and stay busy (2:17, 3:6f)!
Because, in the providence of God, this passage tells us so much about events leading up to the Consummation, it invites a closer look. Once again, my approach will be to give the gist of each section, spotlighting along the way the many indications that Paul here presupposes and teaches a single Consummation at the Parousia of Christ.