The three shipwrecks in 2 Cor. 11:25 were actually before the shipwreck in Act 27, and we know nothing about these three shipwrecks. We know in a severe storm they would throw the cargo into the sea to lighten it load (Jonah 1:5, Acts 27:18-19). This reduced the risk of the ship tearing apart. With heavy clouds and rain in a storm, one couldn't see the positions of the stars and sun; so it would be difficult to navigate. Then, they would lower the sails and drift (Acts 27:17,20). In Acts 27 they were adrift for 14 days (27:27,33).
Commentaries
Thrice I suffered shipwreck (τρις ἐναυαγησα [tris enauagēsa]). First aorist active of ναυαγεω [nauageō], from ναυαγος [nauagos], shipwrecked (ναυς [naus], ship, ἀγνυμι [agnumi], to break). Old and common verb, in N. T. only here and 1 Tim. 1:19. We know nothing of these. The one told in Acts 27 was much later. What a pity that we have no data for all these varied experiences of Paul.
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Robertson, A. T. (1933). Word Pictures in the New Testament (2 Cor. 11:25). Broadman Press.
With respect to the three shipwrecks nothing is said in the Acts (that mentioned in Acts 27. was at a later period).—The νυχθήμερον (24 hours) ἐν τῷ βυθῷ πεποίηκα must have been the consequence of some shipwreck. Not that he had been preserved that length of time in some wonderful manner under the water, but that he had been driven about upon some board or piece of timber or wreck in the midst of the sea, and probably been overwhelmed by the waves.
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Lange, J. P., Schaff, P., Kling, C. F., & Wing, C. P. (2008). A commentary on the Holy Scriptures: 2 Corinthians (p. 187). Logos Bible Software.
Three times I was shipwrecked. Not all Paul’s trials were directly from the hands of men. At times he was tossed about by the convulsions of nature. None of the shipwrecks mentioned here is recorded for us. (The shipwreck in Acts 27 on the way to Rome occurred later in Paul’s history.)
A night and a day I have been in the deep. Again, no experience recorded in Acts seems to answer to this. There is a question whether the deep here refers to a dungeon, or the sea. If it means the sea, was Paul on a raft or in an open boat? If not, he could only have survived such an experience in the water by direct, miraculous intervention by the Lord.
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MacDonald, W. (1995). Believer’s Bible Commentary: Old and New Testaments (A. Farstad, Ed.; p. 1863). Thomas Nelson.