Together, these readings at the Holy Mass this Sunday sing of the most important thing to know about Catholic theology and also a central teaching of the liturgy of the memorial sacrifice; that is, our life in Christ is participatory, or as the author of 2 Peter wrote, those who escape the corruption of the world through Christ “participate in the divine nature,” or as Saint Augustine wrote in Sermo 169, “The God who created you without your cooperation, will not save you without your cooperation.”