Complex sentence: Strict Baptists represent the strain of Particular Baptists that strayed into the "hyper-Calvinistic" course, maintained the practice of strict or closed communion, and remained aloof from the Baptist Union of 1813.
Split into simpler sentences: Strict Baptists represent the strain of Particular Baptists that are often called "hyper-Calvinistic" and maintain the practice of strict or closed communion. They remained aloof from the Baptist Union of 1813.