Kevin DeYoung has written about what it means to him to be called “reformed”. The whole post is very good and you should read it, but I especially liked these two paragraphs.
I delight in the glory of God and in God’s delight for his own glory which brings me, on my best days, unspeakable joy, and on all my other days, still gives purpose and order to an otherwise confusing and seemingly random world.
….
When I say I am Reformed I mean that God is the center of the universe and I am not. I mean that I am a worse sinner than I imagine and God is a greater Savior than I ever thought possible. I mean that the Lord is my righteousness and the Lord alone is my boast. By Reformed I mean all this, and most of all that my only comfort in life and in death is that I am not my own but belong, in body and in soul, to my faithful Savior Jesus Christ, to whom be the glory forever and ever, amen.