Acts 27:9

And when much time was spent, and the voyage was now dangerous, because the Fast was now already gone by, Paul admonished them, and said unto them, Sirs, I perceive that the voyage will be with injury and much loss, not only of the lading and the ship, but also of our lives.

It is altogether possible that Paul was invited to give his opinion; and so we reject the notion that "this prisoner was out of place" in making such remarks. Paul was a man of wide experience, having already suffered shipwreck three times (2 Corinthians 11:25); and the respect in which Julius held Paul makes it nearly certain that Paul's opinion had been asked.

The Fast was gone by ... is a reference to the Jewish Day of Atonement, usually occurring about the time of the autumnal equinox, and thus setting the time here as about October 1. The Mediterranean was not safe for ancient vessels after September 15 until about March 15.

I perceive ... These words suggest that Paul was not speaking in this instance from any inspiration and that he was only giving a personal opinion based upon experience. Even at that, it came frightfully close to being the exact prophecy of what happened, being wrong only in this, that no lives were lost.