66 Here δέ (de) has been translated as “then” to indicate the implied sequence of events within the narrative.
67 This is a reference to the days of the full manifestation of Jesus’ power in a fully established kingdom. The reference to “days” instead of “day” is unusual, appearing only here and in v. 26, but it may be motivated merely by parallelism with the “days” of Noah there and the “days of Lot” in v. 28.

In other versions

And he said to the disciples, “The days are coming when you will desire to see one of the days of the Son of Man, and you will not see it.

Then he said to his disciples, “The time is coming when you will long to see one of the days of the Son of Man, but you will not see it.

Then he told the disciples, “The days are coming when you will long to see one of the days of the Son of Man, but you won’t see it.

Then he said to his disciples, “The time is coming when you will long to see the day when the Son of Man returns, but you won’t see it.

And he said to the disciples, “Days will come when you will desire to see one of the days of the Son of Man, and you will not see it.

And he said unto the disciples, The days will come, when ye shall desire to see one of the days of the Son of man, and ye shall not see it.

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