2 Thessalonians 3:2

Also Paul desired that God would grant him and his colleagues deliverance from unreasonable and harmful unbelievers who sought to limit the spread of the gospel. This is the negative side of the former positive request. To oppose the spread of the gospel is unreasonable behavior since the gospel brings spiritual life to those who are dead in sin. These men were probably unbelieving Jews who were opposing Paul in Corinth (cf. Acts 18:5-6; Acts 18:12-13).

"There is something deeply moving in the thought of this giant among men asking for the prayers of the Thessalonians who so well recognized their own weakness. Nowhere is Paul’s humility more clear to see. And the fact that he, as it were, threw himself on their hearts, must have done much to bind even his opponents to him, because it is very difficult to dislike a man who asks you to pray for him." [Note: Barclay, p. 250.]