when, &c. = no longer bearing it, i.e. able to bear it.
no longer. Greek. meketi.
forbear. bear. See 1 Corinthians 9:12.
thought it good. were well pleased. Same as "were willing" (1 Thessalonians 2:8).
Athens. See Acts 17:15; Acts 17:16. When Silas and Timothy joined Paul, he and Silas must have agreed to dispatch Timothy to Thessalonica, and then Silas must have departed on some other mission. See in 1 Thessalonians 3:5 the change from "we" to "I".