Put a cast iron Dutch oven (or other heavy-bottomed stock pot) over medium-low heat. Add the cumin seeds and toast, stirring often, until the seeds are golden brown and fragrant. Remove the seeds from the heat and grind in a spice grinder or mortar and pestle.
Return the pot to the stove on medium-low heat again and drizzle the olive oil into the pot. Add the onion, celery and carrots and cook, stirring often, until the onions are translucent but not browned and the other vegetables are soft, approximately 8-10 minutes. Add the garlic and stir for another minute, then add the ginger, cinnamon, black pepper and turmeric and continue stirring for a minute or two until the spices are blended and everything is a little sticky looking. Pour in the tomatoes, tomato paste, chickpeas and stir together, bringing everything to a simmer.
Add the stock, rice, Puy lentils, and a handful of the cilantro and parsley leaves. Bring the soup to a boil, then reduce the heat to low, cover and simmer for 20-25 minutes until the rice is cooked and the lentils are tender.
Remove from the heat and stir in more freshly chopped cilantro and parsley. Squeeze in the lemon juice and then serve with more lemon wedges.