John Piper just preached his the second part of his sermon on Romans 15:14-21. The first part was preached on January 29, 2006.
If you'll pull out a calender you'll see the difference between those two dates is (...let's see...30 days has September...carry the 4...) a lot.
Just following in the steps of John Calvin who on Easter Day, 1538, after preaching, he left the pulpit of St. Peter's, banished by the City Council. He returned in September, 1541 – over three years later – and picked up the exposition in the next verse (T. H. L. Parker, Calvin's Preaching, p. 60).