The fact that each one of us has a yearning deep down inside for love, peace and happiness, is a symptom or indication that these things were implanted within us at the very beginning of creation. They were to be the only things we were made up of, but they have practically been extinguished by sin.
Thus, we see symptoms of depression, mental illness, hate and all kinds of evil becoming more and more revealed in our daily lives. When we connect to God, these positive symptoms that lie deep within us, will once again be manifested in our lives, and our negative qualities can be greatly diminish.
Finally, believers, rejoice! Be made complete [be what you should be], be comforted, be like-minded, live in peace [enjoy the spiritual well-being experienced by believers who walk closely with God]; and the God of love and peace [the source of loving kindness] will be with you. 2 Corinthians 13: 11