the days will come = there will come days [for those].
when. All the texts read "and when", following up the Figure of speech Aposiopesis (App-6), as though the time for revealing the fact of His crucifixion had not yet come.
shall be taken away. Greek. apairo. Occurs only here, and the parallels (Mat_9:15. Mar_2:20) implying a violent death; as "lifted up" in Joh_3:14.
then shall they fast. As they did (Act_13:2, Act_13:3).