Great answer Jon and I agree with you that is one of the many things that make us Catholic.
But what makes me 100% Catholic, hmmm, well I’d have to quote Romans (from Paul’s Letters):
“16 For I am not ashamed of the gospel; it is the power of God for salvation to everyone who has faith, to the Jew first and also to the Greek. 17 For in it the righteousness of God is revealed through faith for faith; as it is written, “The one who is righteous will live by faith.””
The Holy Bible : New Revised Standard Version. 1996, c1989 (electronic ed.) (Ro 1:16). Nashville: Thomas Nelson.
I think that truly sums it up for me. Staying in the Gospel, faith in God the father, Jesus the son, and the Holy Spirit, helps us to be righteous and therefore we can live by faith and God’s will.
This in combination with the Eucharist I think is what makes Catholics more in the fullness of Christ. Now that I have said that, I do not mean that non-Catholics are damned or otherwise. Simply we have fullness in Christ, thru Christ, and with Christ that many do not understand and misunderstand.