Vanished Away

After reminding the Thessalonians that before the second coming there first had to come the man of lawlessness sitting in the Temple, he said, "Remember that I told you all these things?" 

That whole topic had been part of the Gospel-message which Paul had originally preached at Thessalonica. 

It was part of Paul's message because it had been part of Jesus's - and because it would fulfil Daniel's. 

The theme had pertinent relevance to the message of the Gospel, because it helped establish the fact that God's Kingdom wouldn't necessarily revolve around theLevitical worship in the Jerusalem Temple. The Kingdom would first be inside you, then afterwards at His coming it will be openly seen - but only by those who are born again. 

Paul really wanted them to know those values, because it reinforced the Gospel of the grace of God as opposed to a salvation through the works of the Law.

Paul was always eager to see that truth established: the Levitical order was passing away. Because if keeping the Law was still seen as a requirement, it made Christ's death meaningless and their faith unfounded. It meant they weren't saved after all.

We today are on the other side of that - the Levitical order isn't still vanishing - it ended when the Temple was destroyed. 

Abraham's promise is sure for all nations - not only for the Jews - because it's by grace not through the Law.