Unless you find oneness, you cannot find joy. You never tire of each other. You can love yourself when your mind and body are in harmony with each other. If you love yourself when Your desire and actions are going different directions, then your love has little meaning. When your mind and body are united into one, then your love will be eternally protected by God.
Unity is the beginning point of love, the point where love can come to abide.
This is God's ideal. Unless God can find persons whose quality is in accordance with His ideal, He cannot be happy at all. He has no one He can love. Since this Principle is the core, we in our movement seek unity first. And then we talk about heart and love.