Combine wheat berries and water with a pinch of salt in a saucepan, and bring to a boil. Reduce heat, and simmer for 60-90 minutes, or until tender. Drain off any excess water, and transfer to a large mixing bowl.
Heat grill to medium high. Brush eggplant slices with 2 tablespoons olive oil. Grill eggplant and tomatoes, turning occasionally, for 8-10 minutes, until eggplant is tender all the way through, and tomato is slightly charred. Transfer all to a cutting board, remove any skin that peels off the tomatoes, and coarsely chop all. Transfer vegetables and all their juices to the mixing bowl with the wheat berries.
In a mortar and pestle, pound together garlic with a pinch of salt to a paste. Whisk in 2 tablespoons olive oil, lemon juice, cumin, coriander and sumac. Heat a small frying pan over medium-low heat, and add paste to pan. Sauté for 2-3 minutes, until fragrant, then whisk in remaining 2 tablespoons oil, and scrape into bowl with wheat berries and vegetables. Toss well, stir in parsley and serve.