Add the onions and garlic, and sauté over medium-low heat until golden.
Add the carrots, celery, and just enough water to cover. Bring to a gentle boil.
Add the green beans, tomatoes, tomato sauce, optional wine, bay leaves, basil, and oregano.
Bring to a simmer, then cover and simmer very gently until the vegetables tender but not overdone, about 40 to 45 minutes.
Meanwhile, cook the orzo in a separate saucepan according to package directions until al dente, then drain.
Stir the cooked orzo, chickpeas, and parsley into the soup. Adjust the consistency with more water if necessary, then season to taste with salt and pepper.
Simmer over very low heat for 5 minutes longer, then serve.