"But as touching brotherly love ye need not that I write unto you:for ye yourselves are taught of God to love one another" (1 Thessalonians 4:8-9).
Our natural love is directly correlated to how we are treated. We find it easy to love people who are kind and loving toward us. But when we find out that someone is dissing us, we find it much harder to love. God loved us while we were his enemy and he requires the same love from us.
No matter how much I try, I fail at this kind of love. So I ask God to love others through me. He answers my prayer in a strange way. He shows me my faults, my failures, and my need for him. When my heart cries out for his mercy and forgiveness, I am suddenly able to have compassion on others who need what I need.
God teaches me how to love through my need for forgiveness.
