Heat the olive oil in a large pot over medium heat. Add the chopped onion and cook for 4 minutes until it softens.
Stir in the minced garlic, oregano, and basil. Cook for 1 minute until the garlic smells fragrant.
Add the rinsed lentils, diced tomatoes with their juice, and vegetable broth. Bring the mixture to a boil.
Reduce the heat to low, cover the pot, and simmer for 20 minutes.
Stir in the shredded cabbage. Continue simmering uncovered for 15 minutes until the lentils are tender and the cabbage is soft.
Season with salt and black pepper. Ladle into bowls and sprinkle with the chopped parsley before serving.