This is a fairly obvious reflection on 1 Corinthians 13:4-7. So much unloving behaviour flows from my felt need to protect myself and my own reputation. I need to look out for number one - how can I possibly have time for being loving? Even resentment or irritability can be traced back to fear about my own identity or the way others perceive me. By reckoning up the wrongs others have done me and meditating on them - which is resentment - I am really just reinforcing my sense of having been in the right myself. By reacting instantly with anger to the slightest crossing of my own will - which is irritability - I reinforce my sense of being at the centre of the universe.
I would need to be so secure, so totally certain that I didn't need to look out for myself, to love in the way the Scripture demands. I would need to really believe that my identity is secure in Christ. I would need to be sure that God sees me truly and loves me unconditionally.
It reminds me a bit of Luther. Luther argued that mediaeval Catholicism had got people so busy chasing after their own justification that they were not able to love others. The money that should have gone to the poor went on indulgences; time that should have been devoted to service of others was wasted in pilgrimages. The Church had people so busy chasing righteousness that they didn't have time to be righteous! If justification were given by grace, on the other hand, and received only by faith - why, then people could be free to live a life of love.