Compare Mark 13:24-27; Luke 21:25-28. Immediately ties the tribulation of those days to the unidentified final tribulation, a tribulation that, on our reading, can be clearly identified as the final one only by the fact that the parousia (Jesus' return) concludes it. Like the day of the Lord in the Old Testament (Amos 5:18-20), Jesus' return is not good news for everyone.