As touching our brother Apollos, I greatly desired him to come unto you with the brethren: but his will was not at all to come at this time; but he will come when he shall have convenient time.
Apollos, I greatly desired him to come unto you. He says this, lest they should suspect that he from jealousy prevented Apollos' coming to them. Perhaps they expressly requested Apollos to be sent to them. Apollos was not at Ephesus when Paul wrote (cf. 1 Corinthians 16:19 and 1 Corinthians 1:1). Probably Apollos' unwillingness to go to Corinth at this time was because he did not wish to sanction his name being made a party cry by those Corinthians who admired his oratory (1 Corinthians 1:12; 1 Corinthians 3:4). Paul's freedom from all selfish jealousy led him to urge Apollos to go: he, of course, could not state in his letter particularly these reasons in the existing divisions there. He calls Apollos "brother," to mark the unity between the two.
With the brethren - who bear this letter (1 Corinthians 16:12; 1 Corinthians 16:17). Conybeare thinks Titus was one of the bearers (2 Corinthians 8:6; 2 Corinthians 8:16-24; 2 Corinthians 12:18).
Convenient (seasonable) time. Apollos did return to Corinth when their divisions were moderated (Jerome).