Bring the quinoa and water to a boil, reduce the temperature to medium-low and simmer, covered, until the liquid has been absorbed, about 15 minutes, and let sit covered for 5 minutes before letting it cool.
Prepare the remaining ingredients.
Mix the quinoa, tomatoes, cucumber, red onion, avocado, feta and chickpeas and toss in the mixture of the lemon juice, oil, oregano, garlic, salt and pepper.