Desmond Adolphus Dacres was born in Saint Andrew Parish (Greater Kingston), Jamaica, on 16 July 1941. Dekker spent his formative years in Kingston. From a young age he regularly attended the local church with his grandmother and aunt. This early religious upbringing, as well as Dekker's enjoyment of singing hymns, led to a lifelong religious commitment. Following his mother's death, he moved to the parish of St. Mary and later to St. Thomas. While at St. Thomas, Dekker embarked on an apprenticeship as a tailor before returning to Kingston, where he became a welder. His workplace singing had drawn the attention of his co-workers, who encouraged him to pursue a career in music. In 1961 he auditioned for Coxsone Dodd (Studio One) and Duke Reid (Treasure Isle), though neither audition was successful. The unsigned vocalist then auditioned for Leslie Kong's Beverley's record label and was awarded his first recording contract.