Albert Barnes on 2 Thessalonians 3:1

Finally, brethren, pray for us. That is, for Paul, Silas, and Timothy, then engaged in arduous labours at Corinth. This request for the prayers of Christians is one which Paul often makes. 1Thes 5:25.

That the word of the Lord may have free course. That is, the gospel. The margin is "run". So also the Greek. The idea is, that it might meet with no obstruction, but that it might be carried abroad with the rapidity of a racer out of whose way every hinderance was removed. The gospel would spread rapidly in the earth if all the obstructions which men have put in its way were removed; and that they may be removed should be one of the constant subjects of prayer.

And be glorified. Be honoured; or appear to be glorious.

As it is with you. It is evident from this Paul met with some obstructions in preaching the gospel where he was then labouring. What they were, he mentions in the next verse. He was then at Corinth, (see the Introduction,) and the history in the Acts of the Apostles informs us of the difficulties which he had to encounter there. See Acts 18.

(1) "free course" "run"