The labours of Calvin were as multiplied and arduous as his achievements were marvellous. The Genevan edition of his works amounts to twelve folio volumes. Besides these, there exist at Geneva two thousand of his sermons and lectures, taken down from his mouth, as he delivered them. He was but twenty-eight years in the ministry altogether.
He was always poor, so as not to be able to have many books. The sufferings of his body from headache, weakness, and other complaints, were constant and intense, so that he was obliged to recline on his couch a part of every day.
It was only the remnants of his time, left from preaching and correspondence, he devoted to study and writing. And yet, every year of his life may be chronicled by his various works. In the midst of convulsions and interruptions of every kind, he pursued his commentaries on the Bible, as if sitting in the most perfect calm, and undisturbed repose.
His labours were indeed incredible, and beyond all comparison. He allowed himself no recreation whatever. He preached and wrote with headaches that would, says Beza, have confined any other person to bed.*
*Calvin and his enemies: A memoir of the life, character, and principles of Calvin. (pp. 25–26).