Well God does help us to do what we can't do ourselves. We don't have in our own nature the ability to be compassionate and kind and humble and gentle and patient like Jesus. But God has given us his Holy Spirit, and we do have the power to change. Not through our own will power, but through greater dependence on Him. And second, God nowhere promises that we can just sit down and wait for a bolt from heaven to strike us into action.
Discipleship is a long hard road.
It's a tough race, and it takes a lot out of us. It's a long distance race, and we won't change completely overnight. But God's promise is that we can change. The clothing is there for us to put on. And sometimes it might be hard to do up the buttons, but we can't sit down and give up.