2 Corinthians 1:1 - Coke's Commentary on the Holy Bible

Timothy our brother,— That is, either in the common faith, (see Romans 1:13 and 1 Corinthians 16:13.) or, brother in the work of the ministry. See Romans 16:21. St. Paul may be supposed to have given Timothy the title of brother here, in this peculiar connection, for dignity's sake, to procure him a reputation above his age among the Corinthians, to whom he had before sent him with some kind of authority to rectify their disorders. Timothy was but a young man when St. Paul wrote his first epistle to him, as appears 1 Timothy 4:12 which epistle, by universal consent, was written to Timothy after he had been at Corinth, and, in the opinion of some very learned men, not less than eight years after; and therefore his calling himbrother here, and joining him with himself in writing his epistle, may be to let the Corinthians see, that, though he who had been sent to them was so young, yet he was one whom St. Paul thought fit to treat as an equal. Achaia was the country in which Corinth stood.