When my children were toddlers, in early months of understandable speech, I welcomed each new word in their vocabularies with joy. Even the word "mine."
Mine is a curious word, because it stirs passion. Our possessions mean something to us. But mine also reveals some of our greatest shortcomings as human beings. After welcoming the word with joy, I realized how difficult it would be to teach sharing to my children. The response to almost any interaction with my toddlers at the time was "mine!" Even with a filled diaper.
If the only barrier to sharing was child-like immaturity. I also realized I'm not the greatest sharer in the world, either. Some things are easier to share than others. Sometimes when Jesus shares something of himself, even his very life, it's easy for me to say, "Well, that's Jesus. Certainly admirable. Certainly something to strive for. But impossible for me."
Paul in his words from Philippians 3 regards all of his pedigrees and accomplishments as garbage. His identity is in Christ. When it gets down to it, I know that my identity is not in my possessions. They come and go. But my memories? My accomplishments? My pedigrees? Sure, some of those memories and "accomplishments" I would like to let go. There's that my/mine word again. Seems I haven't progressed past my toddler years as much as I thought.
The point is not that I flog myself about the good things that have come my way in life. I can even find some joy in them. But that cannot be where my identity is, lest I forget how many people have come together in order that I experience that joy. My identity is in God who claimed my life in Christ. I may never get over my impulse to mark territory and proclaim "mine." Good thing God's claim on me (and) you as "mine" is the most powerful claim of all.