Complex sentence: Christopher's own private sympathies were with the Catholic faith, which his son openly championed; he agreed to shelter the future martyr Edmund Campion in 1569, at the request of Richard Stanyhurst (son of James), Campion's pupil.
Split into simpler sentences: Christopher's own private sympathies were with the Catholic faith, which his son openly championed. He agreed to shelter the future martyr Edmund Campion in 1569, at the request of Richard Stanyhurst (son of James), Campion's pupil.