Thank you for the scientific question on Jonah and the sea creature, “Is it scientifically possible for people to be swallowed by whales just like Jonah in the Bible?”
From what I read, it is highly unlikely that Jonah was swallowed by any typical sea creature as a whale. The Biblical text in Jonah 1 does not state what kind of sea creature that God prepared for Jonah. “For the LORD prepared a great fish to swallow Jonah, and Jonah was inside the fish three days and three nights” (vs.17).
The text does not state what kind of fish/sea creature although many individuals think that it is a form of a whale. From our current understanding of whales, it is not likely that a whale would swallow a man nor he would be able to survive in in for three days and three nights. Having said that, God states that he prepared a fish. It was no ordinary sea creature that God prepared to swallow Jonah. God made it possible for that sea creature to swallow and for Jonah to survive in that sea creature stomach for three days. For in that three days that fish moved toward Nineveh. If God was able to make a plant grow overnight to give shade to Jonah why is it incredible for him to prepare a sea creature to swallow him alive. God was able to cause vegetations and trees to grow and bear fruit in the Garden of Eden. Since God is omnipotent, nothing is impossible for the Creator God.
SUMMARY: A normal sea creature will unlikely be able to swallow a man and for that person to survive in its stomach. A special sea creature prepared by God will be able to swallow a man and God can enable that man to survive in that sea creature’s stomach. Nothing is too hard for God.
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