Eucharist
The bread is the literal body of Christ and the wine is the literal blood of Christ. This is the miracle and mystery of the Eucharist.
I reject Martin Luther's doctrine of consubstantiation which says that the the bread and wine are not the literal body and blood of Christ but that Jesus is present in these elements. Calvin took a similar position but with some nuanced differences.
And I reject Zwingli's doctrine of non-substantiation which reduces the bread and wine to mere symbolism. The majority of Protestants accept his position and are taking an empty Eucharist.
For over 1900 years the Catholic and Eastern Orthodox churches have correctly understood the Eucharist as the literal body and blood of Christ. However, a person can accept this position without having to embrace the doctrine of transubstantiation which was a good faith effort to explain the Eucharist. But how does one explain a miracle and a mystery.