With the exception of Jesus Christ, no one figures more prominently in the pages of the New Testament than the apostle Paul. Author of thirteen New Testament books and a central figure in the book of Acts, Paul was the individual most responsible for the spread of the gospel in the first century.
I read portions in 2008 (for a class on Exposition of Acts); completed in 2022. Hiebert (d. 1995) provides painstaking detail about Paul's companions, from Timothy to Trophimus. This book gives some helpful background information but often gets bogged down responding to conjectures from older commentaries.