"It is because we love [the Church], in a mimesis of the Lord's own love for his Bride [(Eph 5:25-27)], that we submit ourselves to work for the fullest realization of her marks: not only the mark of holiness, which we enhance every time we emerge victorious in the spiritual warfare with the world, the flesh, and the Devil, but the others as well.
"Every time I shape my understanding to the mould found in her dogmatic consciousness or submit myself to the authority of her forms of worship or seek to serve her members in practical ways, I intensify the mark of unity. Whenever I support her missionary activity, by whatever means, or try to bring the culture I have acquired or inherited into symbiotic relation with her life and faith, understanding the latter as fully as my resources will allow, I extend her catholicity. And if in showing others, in word and deed, how I value what has been transmitted to me, in Scripture and Tradition, from the apostles by, for example, kissing the ring—or, if I am a Catholic of the Eastern rites, the hand—of a bishop, I venerate the apostolic hierarchy which joins us in one direction to Pentecost and in another to the Parousia, then on those occasions I enlarge the scope of apostolicity in the Church."
Adrian Nichols, O.P., Figuring out the Church: her marks, and her masters (San Francisco: Ignatius Press, 2013), 176.