Place kamut in a small bowl. Carefully pour boiling water over kamut. Let stand 30 minutes; drain.
Heat oil in a stockpot over medium heat. Add onion, parsley, celery, tarragon, and thyme; cook 10 minutes, stirring occasionally. Add garlic; cook 2 minutes, stirring often.
Add kamut, broth, and bay leaves to onion mixture; bring to a boil. Cover, reduce heat, and simmer 30 minutes. Add lentils and pepper; cook 20 minutes or until lentils are tender. Discard bay leaves. Add chickpeas; simmer 2 minutes. Garnish with celery leaves, if desired.