“The abomination of desolation”
So when you see standing in the holy place 'the abomination of desolation,' described by the prophet Daniel (let the reader understand). (Matthew 24:15 BSB)
What it sounds like today
Apocalyptic code, and it is, but code with a known referent.
The cultural key
The phrase is Daniel's (9:27; 11:31), and for Jesus' hearers it had already happened once: in 167 BC Antiochus IV erected a pagan altar, likely to Olympian Zeus, on the temple's altar and sacrificed swine, the desecration 1 Maccabees calls by this exact name. It ignited the Maccabean revolt; every family retold it at Hanukkah. Jesus reapplies the label to a desecration still coming ('let the reader understand' is a nudge to decode), and Luke's parallel decodes it plainly: 'Jerusalem surrounded by armies.' Within the generation, Rome's standards stood in the burning temple (AD 70); those who fled early survived.
Recovered meaning
'The Antiochus horror will repeat, and when the sacrilege stands in the holy place, don't rally to defend the temple as the Maccabees did. Run.' The instruction reverses the heroic script every hearer was raised on.