The Greek adverb aphnō means suddenly, all at once, or unexpectedly — without warning or preparation. It appears three times in Acts, each time marking a decisive, unexpected divine intervention. The word captures the element of surprise and immediacy that characterizes God's dramatic actions in the book of Acts.
Acts 2:2: 'Suddenly a sound like the blowing of a violent wind came from heaven' — the arrival of the Holy Spirit at Pentecost. Acts 16:26: 'Suddenly there was such a violent earthquake that the foundations of the prison were shaken' — Paul and Silas freed. Acts 28:6: the Maltese expected Paul to 'suddenly' fall dead from the snakebite. In each case, aphnō marks the moment human expectation is overturned by divine action.