I made a typo earlier. Barnabas and Saul are called 'apostles' in Acvts 14:4.
Btw, where does scripture every say receiving special revelation was part and parcel of being an apostle. Do we have any evidence that Barnabas received any special revelation (apart from his name?) How do you define special revelation.
The Bible shows us that Jesus called the 12 apostles. But it also shows as the that Lord can call other men as apostles, too. Where is the scripture that shows the office ceased? Ephesians 4 says that apostles, etc. are given until we all come into the unity of the faith.
About Grundem and the arguments that have gone on in theological discourse, consider the passage from Ephesians 2: 19. Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God; 20. And are built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone;
The church was already built on the apostles and prophets at that point in time, but the roles did not cease in the church. Revelation talked about prophets in a future date (at least from the author's standpoint, no matter which of the major conservative views you take.) Plus, from a local church standpoint, Paul was involved in the foundation of individual churches before and after he wrote this verse, in his churchplanting ministry.