What gives YOU the right?

You know that statement don't you? What makes someone think they have authority/privilege /permission to do something? Regarding Holy Communion... this 1st line of a prayer we'll pray is a tremendous encouragement that our hope and privilege is about Christ and His gospel, not us and our goodness:

WE do not presume to come to this thy Table, o merciful Lord, trusting in our own righteousness, but in thy manifold and great mercies.