His account of having crossed the Coleroon was treated as a lie.

"No mortal man," said the natives, "had ever swum the river; did he but dip a finger in, he would be seized by the alligators," but when evidence proved the fact, the Nabob held up his hands and cried, "This is the man of God." Nevertheless Wilson was chained to a soldier, and, like the well-known David Baird, John Lindsay, and many others, was driven naked, barefoot, and wounded, 500 miles to Seringapatam; where, loaded with irons of thirty-two pounds weight, and chained in couples, they were thrust into a "black hole," and fed so scantily that Wilson declared that at sight of food his jaws snapped together of themselves.
Many a time in the morning corpses were unchained, and the survivors coupled up together again.

Wilson was one of the thirty-one who lived to be released after twenty-two months, in a frightful state of exhaustion and disease.

Afterwards, when commanding a ship at Bencoolen, every European under his command died, and he alone escaped, yet all this time he was an absolute infidel; and, when having made a fortune, he was returning home, he appeared so utterly hardened against all the arguments that the zealous Thomas could bring in favour of Christianity, as to make him in despair remark to the chief officer that he should have more hope of converting the Lascar sailors than of Captain Wilson.
However, the words were penetrating the hitherto ignorant or obdurate heart, and preparing it to attend to further instruction.

After some years of comfort at home, on hearing of plans for a mission to the South Sea Islands, Wilson resolved to offer himself as a free and spontaneous fellow-worker, ready to sacrifice his whole self in the great cause! Meantime Thomas's fervid account of the needs of India had made the infant Society propose to send him out with one colleague; and William Carey, now thirty-three years of age, offered himself as a fellow-worker.
The notion was terrible to Mrs.Carey, who flatly refused to go; but her husband decided on leaving her at home, and only taking his eldest boy, then about ten or eleven years old.