Place freekeh in a bowl and cover with cold water. Set aside.
Combine lamb, onion, pepper, paprika, cinnamon, and salt in a pot. Add oil, 1/2 of the cilantro, 1/2 of the mint, and celery and simmer over low heat for 15 minutes. Stir in chickpeas and cover with a little water. Bring to a gentle simmer. Add tomato paste, zucchini, and carrot and mix well.
Set a steamer over the pot and add tomatoes. Cover and steam tomatoes until soft, about 5 minutes. Crush tomatoes using a wooden spoon so pulp drips into the soup. Discard leftover tomato peels. Add potato and enough water to cover. Simmer until potato is soft, about 10 minutes.
Drain freekeh and add to the soup. Simmer until soft, about 15 minutes. Remove celery stalk. Sprinkle soup with remaining cilantro and mint before serving.