Final answer:
Calvin agreed with Luther on doctrines like salvation by faith and the rejection of the Pope's authority but differed on the doctrine of Predestination.
Step-by-step explanation:
Calvin and Luther were both major figures in the Protestant Reformation and agreed on many doctrines, such as Salvation by faith alone, the rejection of the Pope's authority, and the priesthood of all believers. However, they differed notably on the concept of Predestination. John Calvin believed in predestination, the idea that God has predetermined who will be saved and who will not, regardless of an individual's actions or beliefs. This is a significant difference from Luther's view, which did not assert predestination to the same extent. Calvinism thus emphasized a deterministic view of salvation, contrasting with Luther's emphasis on personal faith for salvation.