On what main point did Ulrich Zwingli's ideas about Christianity differ from Luther's?

Ulrich Zwingli's main point of divergence from Martin Luther's ideas about Christianity centered on the understanding of the Eucharist. While Luther believed in the real presence of Christ in the bread and wine (consubstantiation), Zwingli viewed the Eucharist as a symbolic memorial, emphasizing that it was merely a representation of Christ's body and blood. This fundamental difference in interpretation of sacraments reflected their broader theological disagreements about the nature of faith and salvation.