Work of Faith
The Roman and Greek understanding of fides/pistis(faith) can help clarify the close association between faith and works in these verses. In the relationship between patrons and clients, the client was said to be in the fides/pistis of the patron, for their part clients owed fides/pistis or loyalty to their patron, and this was shown in their actions. The type of work that flowed out of the Thessalonians’ faith is not specified. The word used for work could refer to manual labor (1 Thess. 2:9; 4:11; 2 Thess. 3:8, 10; 1 Cor. 4:12; 9:6) and elsewhere described the ministerial labors of ecclesiastical leaders
Labour of love
As in the previous clause, Paul does not explain what type of labor the Thessalonians undertook. He frequently used the term to refer either to his ministerial labors (e.g., 1 Cor. 3:8; 15:58; 2 Cor. 6:5; 11:23, 27; 1 Thess. 3:5) or to manual labor (1 Thess. 2:9; 2 Thess. 3:8). But here the word most likely refers to any kind of self-sacrificing labor the believers engaged in as they served those both inside and outside the community. Both their faith and love generated labors that were for the benefit of others.
The hope they held was not some vague expectation about a better future but rather solid confidence rooted in the expectation of Christ’s coming. This was the strong foundation that gave the Thessalonians the power to endure and persevere in the face of the tremendous hostility leveled against them.