They are throughout the book of II Thessalonians. They don't imply a soon, only an imminent return. That was the point of Paul's writing. The people of Thessalonica were behaving as the kookburgers of our own times--acting as though Jesus would return and that meant they need not live in the day to day. One of the key themes in Thessalonians was to counter this behavior and teach that, one should act as one wishes to be found acting when Jesus returns, because you don't know when that will occur.