John Calvin Commentary 1 Thessalonians 1:7

"so that ye became an ensample to all that believe in Macedonia and in Achaia." — 1 Thessalonians 1:7 (ASV)

So that you were. Here we have another amplification—that they had stirred up even believers by their example. For it is a great thing to gain such a clear lead over those who had begun the race before us, as to provide assistance to them in continuing their race.

Typus (the word used by Paul) is employed by the Greeks in the same sense as Exemplar is among the Latins, and Patron among the French. He says, then, that the courage of the Thessalonians had been so illustrious that other believers had derived from them a standard of steadfastness.

I preferred, however, to render it patterns, so that I would not needlessly change the Greek phrase used by Paul; and further, because the plural number expresses, in my opinion, something more than if he had said that that Church as a body had been presented for imitation, for the meaning is, that there were as many patterns as there were individuals.