Complex sentence: In 1653 he returned to London to preach at Blackfriar's church after the death of their pastor, William Gouge, and having denounced Cromwell for accepting the office of Lord Protector he was imprisoned.
Split into simpler sentences: In 1653 he returned to London to preach at Blackfriar's church after the death of their pastor, William Gouge. Having denounced Cromwell for accepting the office of Lord Protector, he was imprisoned.