This article consists of notes on Lord's Day 30 of the Heidelberg Catechism.

What is the difference between the Roman Catholic way of celebrating the Lord’s Supper and the Reformed way? Looking at Lord’s Day 30, this article shows that the concept of the Eucharist from the Roman Catholic perspective is based on the continual sacrifice of Christ. Therefore, the Reformed believer cannot participate in the Roman Catholic celebration of the Eucharist.