‘And we have sent together with him the brother whose praise in the gospel is spread through all the churches, and not only so, but who was also appointed by the churches to travel with us in the matter of this grace, which is ministered by us to the glory of the Lord, and to show our readiness.'
And with Titus is coming a man who is highly respected in financial and indeed all matters, among all the churches. His praise with regard to Gospel matters is known throughout the churches. In spiritual terms he is not a nobody. He is the very man selected by the churches to travel with Paul and administer, along with him, the funds being collected, which is an act of service being ministered to the glory of God. The fact that his name is not mentioned may indicate that he was not actually known to the Corinthians. It certainly suggests that he was not one of Paul's companions. (He may temporarily even have forgotten the man's name).
Note the reference to the funds as ‘this grace', this opportunity of showing and demonstrating the work of the grace of God within the givers. This expression of the goodness and love of God, and of His people, is considered as being as important as other ways of making known the Gospel.
‘And to show our readiness.' This man's presence with them as Paul's partner in the enterprise demonstrates Paul's own readiness in the matter.