 The doctrine of justification by faith alone was a direct inheritance from Luther.John Calvin (1509–64), Heinrich Bullinger (1504–75), Wolfgang Musculus (1497–1563), Peter Martyr Vermigli (1500–62), and Andreas Hyperius (1511–64) belong to the second generation of Reformed theologians.Calvin's "Institutes of the Christian Religion" (1536–59) was one of the most influential theologies of the era.