Imagine a glass sitting on a table. You pour water into it and it fills. For a moment you’re distracted and the glass overflows.
Now imagine a whole table full of glasses. You pour water into one. This time, you’re not distracted. You let the glass overflow on purpose and the water spills into the next glass, and then the one after it until the water in the pitcher is spent.
The bigger the pitcher, the more glasses you would fill.
Now imagine that we are all the glasses, a great multitude of glasses that no one can count, and God is holding the pitcher. The water is his superabundant grace, and his pitcher is never empty.
That’s what it is to be the be the Communion of Saints. Each of us is a vessel made by God. He makes us each empty so he can fill us with his grace, and he brings us together, in the Church that his Son Jesus Christ founded, so that we may overflow with his grace and fill one another as well.
That is what it is to be a saint. To be a vessel overflowing with grace. That is what we are all called to be.