Though close to the Pharisees in greatest-commandment, big-picture theology, He condemns their application of the Word to life, which is mixed throughout with pride. They major on minors and externals (which are not synonymns, though).
Jesus speaks of the day the Temple will be destroyed (not His yet-future, second coming to judge all men). He describes the Jews' rejection of His apostles after His ascension, leading up to God's rejection of the Jews, leaving them to the armies of Rome. They will be redeemed from the Messiah-rejecting nation of Israel, when the latter is brought low. Once again, God's people will be judged for her sin by a more pagan nation, with a faithful remnant left to glorify Him. Stay awake so this judgment doesn't catch you by surprise.
We stay awake by staying filled with the Spirit (oil), which enables us to steward the master's resources wisely, by feeding the hungry, clothing the naked and visiting those in distress.