What were the differences between Martin Luther and John Calvin?
The major difference between Luther and Calvin had been the issue of predestination. Luther had argued that salvation came from faith alone; that good works were not necessary and that salvation was available to all. Faith reconciled one to God. Calvin believed that God had all men were depraved sinners who deserved God's judgement; but God had determined from the beginning of the world that certain persons had been "predestined" to be saved:
Predestination we call the eternal decree of God by which He determined in Himself what would have to become of every individual of mankind. For they are not all created with a similar destiny; but eternal life is foreordained for some and eternal damnation for others. Every person, therefore, being created for one or the other of these two ends, we say is predestined to life or to death.
Calvin and Luther also disagreed over the significance of Holy Communion. Luther held firm to the theory of transubstantiation; that is the bread and wine were transformed into the actual body and blood of Christ. In fact, when a meeting was held between Luther and Ulrich Zwingli in an attempt to resolve religious differences, Luther struck the table with his fist before storming out of the room shouting Hoc Est Mea Corpus! ("this is my body.") Calvin argued that there was a something of a spiritual presence of Christ at the Communion. Salvation and the communion host were so closely related that one could:
“easily pass from one to the other. For why should the Lord put in your hand the symbol of his body unless it was to assure you that you really participate in it?”