Week 42 Acts
Acts two picks-up-the-pace: suddenly a sound like the blowing of a violent wind came from heaven and filled the whole house where (the apostles) were sitting. They saw what seemed to be tongues of fire that separated and came to rest on each of them. All of them were filled with the Holy Spirit and began to speak in other tongues as the Spirit enabled them.
I figure this event registered with the apostles as a big & unexpected surprise – i.e. unexpected in how the incident actually played out in actual life. It couldn’t have been a total-total surprise since John the Baptist had publicly said: after me will come one who is more powerful than I…He will baptize you with the Holy Spirit and fire… So it’s not like the Holy Spirit’s fire-baptism came out of the blue (and besides the Lord had personally told the apostles the same thing as he was leaving: do not leave Jerusalem, but wait for the gift my Father promised, which you have heard me speak about…In a few days you will be baptized with the Holy Spirit).
So the apostles did have a theoretical expectation of what was coming. But the here-and-now practical & personal experience of the Spirit – the thundering gale-force winds & the incandescent tongue-like objects & the linguistic enhancements – those weren’t exactly anticipated.
Note: quotes from Acts 2:2-4, Matthew 3:11 (also Mark 1:8, Luke 3:16, John 1:33), Acts 1:4-5 (NIV)