II.
(1) For yourselves brethren, know. — The writers’ purpose is practical, not didactic; they there-fore animate their converts with the stirring memories of their conversion. “We need not go to these foreign witnesses for the tale of how we came to you; for you recollect it as if it were yesterday.” The “for” (as in 1 Thessalonians 1:8) implies “for in fact,” “for after all.” The thought of 1 Thessalonians 1:5; 1 Thessalonians 1:9. is here resumed, but with a different purpose: there it was to prove that the work was God’s work; here, “to stir up their pure minds by way of remembrance.”
Not in vain draws a little too much attention to the result of their coming. It should be, not vain — i.e., not purposeless and idle. This may be seen from the contrast drawn in the following words.