i. Silvanus (also known as Silas) was a long and experienced companion of Paul. He traveled with Paul on his second missionary journey and was imprisoned and set free with Paul in the Philippian jail (Acts 16:19-24). When Paul first came to Thessalonica, Silas came with him (Acts 17:1-9), so the Thessalonians knew Silvanus well.

ii. Timothy was a resident of Lystra, a city in the province of Galatia (Acts 16:1-3). He was the son of a Greek father (Acts 16:2), and a Jewish mother named Eunice (2 Timothy 2:5). From his youth, he had been taught in the Scriptures by his mother and grandmother (2 Timothy 1:5; 3:15). Timothy was a trusted companion and associate of Paul, and he accompanied Paul on many of his missionary journeys. Paul sent Timothy to the Thessalonians on a previous occasion (1 Thessalonians 3:2).