With Thomas Coke and James Lyons, another Irish preacher, he sailed for the West Indies in October 1790. (References to Lyons are few and unclear. He was left at Barbados with instructions to join Coke at St. Kitts, but two years later was removed from the stations because of 'unworthiness'.) Arriving at St. Vincent with Coke, Worrell was impressed by the natural beauty of mountain, sea and coconut palms, and the coffee and cotton plantations. Coke wrote that Worrell was 'so charmed with the prospects, that he confessed he felt himself perfectly reconciled to the West-Indies'. Arriving in Jamaica in January 1791, they were given details of the persecution of Methodists by white settlers and found William Hammet broken in health. Coke and Hammet sailed for Charleston, SC, leaving Worrell in Jamaica. At first he had little success in Spanish Town and Port Royal, but fared better in Kingston. In addition to his Sunday duties, he led classes and preached five nights a week and almost every morning. On being advised that he was working too hard in tropical conditions, he replied that he could not 'rob God of his due'. On the morning of 6 November 1791 he preached on 'Fear not, little flock,' after which he felt tired and feverish. Later he preached on 'Fight the good fight,' and again next morning. After a week's illness he 'died the death of a saint' on 15 November. With Hammet and Lyons, he illustrates the uncertainty and cost of early missionary endeavours in the tropics.